#2466 Gradle build now checks that user has JDK with bundled JavaFX libraries installed

Co-authored-by: denny <dennis.sheirer@gmail.com>

.github/workflows/gradle.yml

@@ -22,10 +22,10 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
-      - name: Set up JDK 25
+      - name: Set up JDK 27
         uses: actions/setup-java@v3
         with:
-          java-version: '25'
+          java-version: '27'
           distribution: 'liberica'
           java-package: 'jdk+fx'
       - name: Build with Gradle

.github/workflows/nightly.yml

@@ -15,10 +15,11 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Set up JDK 25
+      - name: Set up JDK 27
         uses: actions/setup-java@v3
         with:
-          java-version: '25'
+          # Must match the JDK version downloaded in build.gradle (jdk_download_base) - jlink requires an exact version match
+          java-version: '27.0.0'
           distribution: 'liberica'
           java-package: 'jdk+fx'
 
@@ -37,11 +38,12 @@ jobs:
           echo -e "ref: $GITHUB_REF \ncommit: $GITHUB_SHA\nbuild: $(date +"%Y-%m-%dT%H:%M:%SZ")" > build/image/build_info.txt
 
       - name: Add build artifacts to nightly release
-        uses: pyTooling/Actions/releaser@main
+        uses: softprops/action-gh-release@v2
         with:
-          tag: nightly
-          rm: false
-          token: ${{ secrets.GITHUB_TOKEN }}
+          tag_name: nightly
+          prerelease: true
           files: |
             build/image/*.zip
             build/image/build_info.txt
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.idea/misc.xml

@@ -4,7 +4,50 @@
   <component name="FrameworkDetectionExcludesConfiguration">
     <file type="web" url="file://$PROJECT_DIR$" />
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_25_PREVIEW" project-jdk-name="liberica-25" project-jdk-type="JavaSDK">
+  <component name="NullableNotNullManager">
+    <option name="myDefaultNullable" value="org.jetbrains.annotations.Nullable" />
+    <option name="myDefaultNotNull" value="org.jetbrains.annotations.NotNull" />
+    <option name="myOrdered" value="true" />
+    <option name="myNullables">
+      <value>
+        <list size="13">
+          <item index="0" class="java.lang.String" itemvalue="org.jspecify.annotations.Nullable" />
+          <item index="1" class="java.lang.String" itemvalue="org.jetbrains.annotations.Nullable" />
+          <item index="2" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.qual.Nullable" />
+          <item index="3" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NullableDecl" />
+          <item index="4" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NullableType" />
+          <item index="5" class="java.lang.String" itemvalue="org.eclipse.jdt.annotation.Nullable" />
+          <item index="6" class="java.lang.String" itemvalue="edu.umd.cs.findbugs.annotations.Nullable" />
+          <item index="7" class="java.lang.String" itemvalue="javax.annotation.Nullable" />
+          <item index="8" class="java.lang.String" itemvalue="javax.annotation.CheckForNull" />
+          <item index="9" class="java.lang.String" itemvalue="io.reactivex.annotations.Nullable" />
+          <item index="10" class="java.lang.String" itemvalue="io.reactivex.rxjava3.annotations.Nullable" />
+          <item index="11" class="java.lang.String" itemvalue="org.springframework.lang.Nullable" />
+          <item index="12" class="java.lang.String" itemvalue="jakarta.annotation.Nullable" />
+        </list>
+      </value>
+    </option>
+    <option name="myNotNulls">
+      <value>
+        <list size="13">
+          <item index="0" class="java.lang.String" itemvalue="org.jspecify.annotations.NonNull" />
+          <item index="1" class="java.lang.String" itemvalue="org.jetbrains.annotations.NotNull" />
+          <item index="2" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.qual.NonNull" />
+          <item index="3" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NonNullDecl" />
+          <item index="4" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NonNullType" />
+          <item index="5" class="java.lang.String" itemvalue="org.eclipse.jdt.annotation.NonNull" />
+          <item index="6" class="java.lang.String" itemvalue="edu.umd.cs.findbugs.annotations.NonNull" />
+          <item index="7" class="java.lang.String" itemvalue="javax.annotation.Nonnull" />
+          <item index="8" class="java.lang.String" itemvalue="lombok.NonNull" />
+          <item index="9" class="java.lang.String" itemvalue="io.reactivex.annotations.NonNull" />
+          <item index="10" class="java.lang.String" itemvalue="io.reactivex.rxjava3.annotations.NonNull" />
+          <item index="11" class="java.lang.String" itemvalue="org.springframework.lang.NonNull" />
+          <item index="12" class="java.lang.String" itemvalue="jakarta.annotation.Nonnull" />
+        </list>
+      </value>
+    </option>
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_27_PREVIEW" project-jdk-name="liberica-27" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>

build.gradle

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2025 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,16 +17,18 @@
  * ****************************************************************************
  */
 
+import org.beryx.runtime.RuntimeZipTask
+import org.gradle.internal.jvm.Jvm
+import org.gradle.nativeplatform.platform.internal.DefaultNativePlatform
+
 import java.text.SimpleDateFormat
 
-
-
 /**
  * Instructions for building/compiling the sdrtrunk application.
  *
  * Prerequisites:
- * Install and configure an OpenJDK version 22+ that includes the JavaFX modules (e.g. Bellsoft Liberica JDK)
- * - Optional: install and configure Gradle 8.10+
+ * Install and configure an OpenJDK version 27+ that includes the JavaFX modules (e.g. Bellsoft Liberica JDK)
+ * - Optional: install and configure Gradle 9.8+
  *
  * Scenario 1: run the application via gradle command line from the source code root directory:
  * command: ./gradlew run
@@ -50,24 +52,40 @@ plugins {
     id 'org.beryx.runtime' version '2.0.1'
 }
 
-repositories {
-    mavenCentral()
-    maven { url = "https://jitpack.io" }
-}
-
 //Version is defined in gradle.properties so that we can CLI override it for nightly builds.
 version = project.findProperty('projectVersion')
 
-//Java 24 is required for this version of the Project Panama preview/incubator feature
+//Java 27 is required for this version of the Project Panama preview/incubator feature
 java {
     toolchain {
-        languageVersion = JavaLanguageVersion.of(25)
+        languageVersion = JavaLanguageVersion.of(27)
+        vendor = JvmVendorSpec.BELLSOFT
     }
 }
 
-sourceSets {
-    main.java.srcDirs 'src/main'
-    test.java.srcDirs 'src/test'
+/**
+ * Verifies that the selected toolchain JDK includes the JavaFX modules (e.g. Bellsoft Liberica 'Full JDK').
+ *
+ * Gradle's toolchain spec can only select by language version, vendor and implementation, so it can't distinguish
+ * between the Liberica JDK packages that do and don't bundle JavaFX. This task fails the build with a clear message
+ * instead of allowing compilation to fail with missing javafx packages.
+ */
+tasks.register('verifyToolchainJavaFx') {
+    def jdkHome = javaToolchains.launcherFor(java.toolchain).map { it.metadata.installationPath.asFile }
+
+    doLast {
+        def release = new File(jdkHome.get(), 'release')
+
+        if(!release.exists() || !release.text.contains('javafx.base')) {
+            throw new GradleException("The JDK at [${jdkHome.get()}] does not include the JavaFX modules. Install " +
+                    "the Bellsoft Liberica JDK 27 'Full' package (includes LibericaFX), or use " +
+                    "-Porg.gradle.java.installations.paths=<jdk path> to specify the JDK that Gradle should use.")
+        }
+    }
+}
+
+tasks.named('compileJava') {
+    dependsOn 'verifyToolchainJavaFx'
 }
 
 test {
@@ -85,37 +103,41 @@ dependencies {
 
     //Jitpack imports
     implementation 'com.github.dnault:libresample4j:master'
-    implementation 'com.github.DSheirer.jmbe:jmbe-api:1.0.0'
+    implementation 'com.github.DSheirer.jmbe:api:v2.1.0'
     implementation 'com.github.nwaldispuehl:java-lame:v3.98.4'
 
     //mavenCentral/jcenter imports
-    implementation 'ch.qos.logback:logback-classic:1.5.21'
-    implementation 'ch.qos.logback:logback-core:1.5.21'
-    implementation 'com.fasterxml.jackson.dataformat:jackson-dataformat-xml:2.20.1'
+    implementation 'ch.qos.logback:logback-classic:1.6.3'
+    implementation 'ch.qos.logback:logback-core:1.5.38'
+    implementation 'com.fasterxml.jackson.dataformat:jackson-dataformat-xml:2.22.4'
     implementation 'com.fazecast:jSerialComm:2.11.4'
+    implementation 'com.formdev:flatlaf:3.7.2'
+    implementation 'com.formdev:flatlaf-intellij-themes:3.7.2'
     implementation 'com.github.jiconfont:jiconfont-font_awesome:4.7.0.1'
     implementation 'com.github.jiconfont:jiconfont-javafx:1.0.0'
     implementation 'com.github.jiconfont:jiconfont-swing:1.0.1'
-    implementation 'com.github.wendykierp:JTransforms:3.1'
-    implementation 'com.google.code.gson:gson:2.13.2'
-    implementation 'com.google.guava:guava:33.5.0-jre'
+    implementation 'com.github.wendykierp:JTransforms:3.2'
+    implementation 'com.google.code.gson:gson:2.14.0'
+    implementation 'com.google.guava:guava:33.6.0-jre'
     implementation 'com.jidesoft:jide-oss:3.6.18'
-    implementation 'com.miglayout:miglayout-swing:11.4.2'
+    implementation 'com.miglayout:miglayout-swing:11.4.3'
     implementation 'com.mpatric:mp3agic:0.9.1'
-    implementation 'commons-io:commons-io:2.21.0'
+    implementation 'commons-io:commons-io:2.22.0'
     implementation 'eu.hansolo:charts:1.0.5'
+    implementation 'io.github.dsheirer:jbladerf:2.6.0' //bladeRF tuners - GitHub release, see settings.gradle
+    implementation 'io.github.dsheirer:jhydrasdr:1.1.3' //HydraSDR tuners - GitHub release, see settings.gradle
     implementation 'io.github.dsheirer:radio-reference-api:18.0.0'
     implementation 'io.github.dsheirer:usb4java-native-libraries:1.3.3' //OSX & Windows aarch64 native libs
     implementation 'io.github.dsheirer:usb4java:1.3.5' //Fork with Loader support for OSX Multi-Version
     implementation 'javax.usb:usb-api:1.0.2'
     implementation 'net.coderazzi:tablefilter-swing:5.5.4'
     implementation 'org.apache.commons:commons-compress:1.28.0'
-    implementation 'org.apache.commons:commons-lang3:3.19.0'
+    implementation 'org.apache.commons:commons-lang3:3.20.0'
     implementation 'org.apache.commons:commons-math3:3.6.1'
     implementation 'org.apache.commons:commons-csv:1.14.1'
-    implementation 'org.apache.mina:mina-core:2.2.4'
-    implementation 'org.apache.mina:mina-http:2.2.4'
-    implementation 'org.controlsfx:controlsfx:11.2.2'
+    implementation 'org.apache.mina:mina-core:2.2.9'
+    implementation 'org.apache.mina:mina-http:2.2.9'
+    implementation 'org.controlsfx:controlsfx:11.2.3'
     implementation 'org.rauschig:jarchivelib:1.2.0'
     implementation 'org.slf4j:slf4j-api:2.0.17'
     implementation 'org.usb4java:libusb4java:1.3.0'
@@ -123,12 +145,12 @@ dependencies {
     implementation 'pl.edu.icm:JLargeArrays:1.6'
 }
 
-def os = org.gradle.nativeplatform.platform.internal.DefaultNativePlatform.currentOperatingSystem
+def os = DefaultNativePlatform.currentOperatingSystem
 
 /**
- * This is needed for the JDK23 vector API ... until it moves out of incubation or preview
+ * This is needed for the JDK23+ vector API ... until it moves out of incubation or preview
  */
-tasks.withType(JavaCompile) {
+tasks.withType(JavaCompile).configureEach {
     options.compilerArgs.add("--enable-preview") //Project Panama Vector API is still in incubator
     options.compilerArgs.add("--add-modules=jdk.incubator.vector") //Project Panama Vector API is still in incubator
 }
@@ -139,12 +161,11 @@ tasks.withType(JavaCompile) {
 def jvmArgsWindows =
         ['--add-exports=javafx.base/com.sun.javafx.event=ALL-UNNAMED', //Needed for controls-fx.jar
          '--add-exports=java.desktop/com.sun.java.swing.plaf.windows=ALL-UNNAMED', //windows users for JIDE
-         '--add-modules=jdk.incubator.vector',   //Project Panama Vector API is still in incubator
+         '--add-modules=jdk.incubator.vector',   //Project Panama vector API is still in incubator
          '--enable-preview', //Project Panama Vector API is still in incubator
          '--enable-native-access=ALL-UNNAMED', //Suppress unsafe warnings for FFM API Foreign Memory calls
          '--enable-native-access=javafx.graphics', //JDK24 - suppress restricted java.lang.System calls
          '--sun-misc-unsafe-memory-access=allow', //JDK24 - suppress sun.misc.Unsafe::allocateMemory warning
-         '-XX:+UseCompactObjectHeaders',   //JDK25 - use compact object headers
          '-Djava.library.path=c:\\Program Files\\SDRplay\\API\\x64'] //SDRPlay API library path
 
 /**
@@ -152,10 +173,9 @@ def jvmArgsWindows =
  */
 def jvmArgsLinux =
         ['--add-exports=javafx.base/com.sun.javafx.event=ALL-UNNAMED', //Needed for controls-fx.jar
-         '--add-modules=jdk.incubator.vector',   //Needed while Project Panama API is still in incubator
+         '--add-modules=jdk.incubator.vector',   //Project Panama vector API is still in incubator
          '--enable-preview', //Project Panama Vector & Foreign Function APIs remain in incubator
          '--sun-misc-unsafe-memory-access=allow', //JDK24 - suppress sun.misc.Unsafe::allocateMemory warning
-         '-XX:+UseCompactObjectHeaders',   //JDK25 - use compact object headers
          '--enable-native-access=javafx.graphics', //JDK24 - suppress restricted java.lang.System calls
          '--enable-native-access=ALL-UNNAMED'] //SDRPlay API library path
 
@@ -229,7 +249,7 @@ String jdk_windows_aarch64 = jdk_base + 'windows-arm64/jdk-25.0.1-full'
 /**
  * Download URLs to download the JDK as part of the gradle build packaging process
  */
-def jdk_download_base = "https://download.bell-sw.com/java/25.0.1+11/bellsoft-jdk25.0.1+11-"
+def jdk_download_base = "https://download.bell-sw.com/java/27+36/bellsoft-jdk27+36-"
 def jdk_download_suffix = "-full.tar.gz"
 def jdk_download_linux_aarch64 = jdk_download_base + "linux-aarch64" + jdk_download_suffix
 def jdk_download_linux_x86_64 = jdk_download_base + "linux-amd64" + jdk_download_suffix
@@ -244,16 +264,17 @@ def jdk_download_windows_aarch64 = jdk_download_base + "windows-aarch64-full.zip
  * @param jvmArgs to use (windows or linux)
  * @return configured task.
  */
-def configure(org.beryx.runtime.RuntimeZipTask rt, List<String> jvmArgs) {
+def configure(RuntimeZipTask rt, List<String> jvmArgs) {
     //Use the correct set of JVM arguments
     rt.extension.launcherData.get().jvmArgs = jvmArgs
 
     //Additional modules to include with auto-detected modules.
+    //jdk.charsets - NXDN BIG5 encoding support
     //jdk.crypto.ec - needed for HTTPS connections (broadcastify calls & map tile server)
     //jdk.incubator.vector - needed for Project Panama foreign function and vector apis
     //jdk.accessibility is used with assistive technologies like screen readers
     //java.management for JVM resource monitoring
-    rt.extension.addModules('jdk.crypto.ec', 'jdk.incubator.vector', 'jdk.accessibility', 'java.management')
+    rt.extension.addModules('jdk.charsets', 'jdk.crypto.ec', 'jdk.incubator.vector', 'jdk.accessibility', 'java.management')
 
     //Use auto-detected modules and 'add' any specified modules.
     rt.extension.additive.set(true)
@@ -262,7 +283,8 @@ def configure(org.beryx.runtime.RuntimeZipTask rt, List<String> jvmArgs) {
     rt.extension.addOptions('--strip-debug', '--compress', '2', '--no-header-files', '--no-man-pages')
 
     //Runtime images have auto appended version in image zip name.  Override to include version in single target image.
-    rt.extension.imageZip.set(file("$buildDir/image/sdr-trunk.zip"))
+//    rt.extension.imageDir=layout.buildDirectory.dir('image')
+    rt.extension.imageZip.set(file(layout.buildDirectory.dir('image').get().file('sdr-trunk.zip')))
 }
 
 /**
@@ -274,35 +296,35 @@ def configure(org.beryx.runtime.RuntimeZipTask rt, List<String> jvmArgs) {
  * Usage: gradlew runtimeZipCurrent   (windows - using gradlew)
  * Usage: ./gradlew runtimeZipCurrent   (linux - using gradlew)
  */
-tasks.register('runtimeZipCurrent', org.beryx.runtime.RuntimeZipTask) {rt ->
+tasks.register('runtimeZipCurrent', RuntimeZipTask) {rt ->
     def arch = System.properties.getProperty("os.arch")
-    def javaHome = org.gradle.internal.jvm.Jvm.current().getJavaHome().toString()
+    def javaHome = Jvm.current().getJavaHome().toString()
 
     if(os.isWindows()) {
-        if(arch.equals("amd64")) {
+        if(arch == "amd64") {
             rt.extension.targetPlatform(targetWindowsX86_64, javaHome)
         }
-        else if(arch.equals("aarch64")) {
+        else if(arch == "aarch64") {
             rt.extension.targetPlatform(targetWindowsAarch64, javaHome)
         }
         configure(rt, jvmArgsWindows)
     }
     else if(os.isLinux())
     {
-        if(arch.equals("amd64")) {
+        if(arch == "amd64") {
             rt.extension.targetPlatform(targetLinuxX86_64, javaHome)
         }
-        else if(arch.equals("aarch64")) {
+        else if(arch == "aarch64") {
             rt.extension.targetPlatform(targetLinuxAarch64, javaHome)
         }
         configure(rt, jvmArgsLinux)
     }
     else if(os.isMacOsX())
     {
-        if(arch.equals("amd64")) {
+        if(arch == "amd64") {
             rt.extension.targetPlatform(targetOsxX86_64, javaHome)
         }
-        else if(arch.equals("aarch64")) {
+        else if(arch == "aarch64") {
             rt.extension.targetPlatform(targetOsxAarch64, javaHome)
         }
         configure(rt, jvmArgsLinux)
@@ -319,7 +341,7 @@ tasks.register('runtimeZipCurrent', org.beryx.runtime.RuntimeZipTask) {rt ->
  * Usage: gradlew runtimeZipWindows   (windows - using gradlew)
  * Usage: ./gradlew runtimeZipWindows   (linux - using gradlew)
  */
-tasks.register('runtimeZipWindows', org.beryx.runtime.RuntimeZipTask) {rt ->
+tasks.register('runtimeZipWindows', RuntimeZipTask) {rt ->
     //Windows aarch64
     if(file(jdk_windows_aarch64).exists()) {
         rt.extension.targetPlatform(targetWindowsAarch64, jdk_windows_aarch64, [])
@@ -351,7 +373,7 @@ tasks.register('runtimeZipWindows', org.beryx.runtime.RuntimeZipTask) {rt ->
  * Usage: gradlew runtimeZipOthers   (windows - using gradlew)
  * Usage: ./gradlew runtimeZipOthers   (linux - using gradlew)
  */
-tasks.register('runtimeZipOthers', org.beryx.runtime.RuntimeZipTask) {rt ->
+tasks.register('runtimeZipOthers', RuntimeZipTask) {rt ->
     //Linux aarch64
     if(file(jdk_linux_aarch64).exists()) {
         rt.extension.targetPlatform(targetLinuxAarch64, jdk_linux_aarch64, [])

gradle.properties

@@ -1,6 +1,6 @@
 #
 # ******************************************************************************
-# Copyright (C) 2014-2024 Dennis Sheirer
+# Copyright (C) 2014-2026 Dennis Sheirer
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

gradle/wrapper/gradle-wrapper.properties

@@ -1,26 +1,9 @@
-#
-# ******************************************************************************
-# Copyright (C) 2014-2025 Dennis Sheirer
-#
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>
-# *****************************************************************************
-#
-
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.2.0-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.8.1-bin.zip
 networkTimeout=10000
+retries=0
+retryBackOffMs=500
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

gradlew

@@ -1,27 +1,26 @@
 #!/bin/sh
 
 #
-# ******************************************************************************
-# Copyright (C) 2014-2025 Dennis Sheirer
+# Copyright © 2015 the original authors.
 #
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
 #
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
+#      https://www.apache.org/licenses/LICENSE-2.0
 #
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>
-# *****************************************************************************
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
 #
 
 ##############################################################################
 #
-#   Gradle start up script for POSIX generated by Gradle.
+#   gradlew start up script for POSIX generated by Gradle.
 #
 #   Important for running:
 #
@@ -30,7 +29,7 @@
 #       bash, then to run this script, type that shell name before the whole
 #       command line, like:
 #
-#           ksh Gradle
+#           ksh gradlew
 #
 #       Busybox and similar reduced shells will NOT work, because this script
 #       requires all of these POSIX shell features:
@@ -58,7 +57,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/3d91ce3b8caaf77ad09f381f43615b715b53f72c/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.
@@ -115,7 +114,6 @@ case "$( uname )" in                #(
   NONSTOP* )        nonstop=true ;;
 esac
 
-CLASSPATH="\\\"\\\""
 
 
 # Determine the Java command to use to start the JVM.
@@ -173,7 +171,6 @@ fi
 # For Cygwin or MSYS, switch paths to Windows format before running java
 if "$cygwin" || "$msys" ; then
     APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
-    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
 
     JAVACMD=$( cygpath --unix "$JAVACMD" )
 
@@ -213,7 +210,6 @@ DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
-        -classpath "$CLASSPATH" \
         -jar "$APP_HOME/gradle/wrapper/gradle-wrapper.jar" \
         "$@"
 

gradlew.bat

@@ -19,12 +19,12 @@
 @if "%DEBUG%"=="" @echo off
 @rem ##########################################################################
 @rem
-@rem  Gradle startup script for Windows
+@rem  gradlew startup script for Windows
 @rem
 @rem ##########################################################################
 
-@rem Set local scope for the variables with windows NT shell
-if "%OS%"=="Windows_NT" setlocal
+@rem Set local scope for the variables, and ensure extensions are enabled
+setlocal EnableExtensions
 
 set DIRNAME=%~dp0
 if "%DIRNAME%"=="" set DIRNAME=.
@@ -51,7 +51,7 @@ echo. 1>&2
 echo Please set the JAVA_HOME variable in your environment to match the 1>&2
 echo location of your Java installation. 1>&2
 
-goto fail
+"%COMSPEC%" /c exit 1
 
 :findJavaFromJavaHome
 set JAVA_HOME=%JAVA_HOME:"=%
@@ -65,30 +65,18 @@ echo. 1>&2
 echo Please set the JAVA_HOME variable in your environment to match the 1>&2
 echo location of your Java installation. 1>&2
 
-goto fail
+"%COMSPEC%" /c exit 1
 
 :execute
 @rem Setup the command line
 
-set CLASSPATH=
 
 
-@rem Execute Gradle
-"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %*
+@rem Execute gradlew
+@rem endlocal doesn't take effect until after the line is parsed and variables are expanded
+@rem which allows us to clear the local environment before executing the java command
+endlocal & "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %* & call :exitWithErrorLevel
 
-:end
-@rem End local scope for the variables with windows NT shell
-if %ERRORLEVEL% equ 0 goto mainEnd
-
-:fail
-rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
-rem the _cmd.exe /c_ return code!
-set EXIT_CODE=%ERRORLEVEL%
-if %EXIT_CODE% equ 0 set EXIT_CODE=1
-if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
-exit /b %EXIT_CODE%
-
-:mainEnd
-if "%OS%"=="Windows_NT" endlocal
-
-:omega
+:exitWithErrorLevel
+@rem Use "%COMSPEC%" /c exit to allow operators to work properly in scripts
+"%COMSPEC%" /c exit %ERRORLEVEL%

settings.gradle

@@ -1 +1,28 @@
-rootProject.name = 'sdr-trunk'
+plugins {
+    id 'org.gradle.toolchains.foojay-resolver-convention' version '1.0.0'
+}
+rootProject.name = 'sdr-trunk'
+
+dependencyResolutionManagement {
+    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
+    repositories {
+        mavenCentral()
+        maven { url 'https://jitpack.io' }
+
+        //jHydraSDR is published as a GitHub release, with the native libraries for all platforms in the jar
+        ivy {
+            url = 'https://github.com/DSheirer/jHydraSDR/releases/download'
+            patternLayout { artifact 'v[revision]/[artifact]-[revision].[ext]' }
+            metadataSources { artifact() }
+            content { includeModule 'io.github.dsheirer', 'jhydrasdr' }
+        }
+
+        //jBladeRF is published as a GitHub release, with the native libraries for all platforms in the jar
+        ivy {
+            url = 'https://github.com/DSheirer/jBladeRF/releases/download'
+            patternLayout { artifact 'v[revision]/[artifact]-[revision].[ext]' }
+            metadataSources { artifact() }
+            content { includeModule 'io.github.dsheirer', 'jbladerf' }
+        }
+    }
+}

src/main/java/com/sun/java/swing/plaf/windows/WindowsLookAndFeel.java

@@ -0,0 +1,81 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package com.sun.java.swing.plaf.windows;
+
+import javax.swing.LookAndFeel;
+import javax.swing.UIDefaults;
+
+/**
+ * No-op stub for the JDK's Windows look-and-feel.
+ *
+ * <p>JIDE 3.6.18's {@code LookAndFeelFactory} contains compile-time
+ * {@code instanceof com.sun.java.swing.plaf.windows.WindowsLookAndFeel} checks throughout its
+ * dispatch logic.  On Linux and macOS JDK builds that class is genuinely absent from
+ * {@code java.desktop}, so the JVM throws {@link NoClassDefFoundError} the first time JIDE's
+ * dispatch code executes the {@code instanceof} bytecode.  That happens during
+ * {@link com.jidesoft.swing.JideSplitPane#updateUI()} on every LAF change.
+ *
+ * <p>This stub lives in the classpath so the class reference resolves on non-Windows JDKs.
+ * On Windows JDK builds the real {@code WindowsLookAndFeel} is loaded from the
+ * {@code java.desktop} module via the boot class loader and shadows this class.
+ *
+ * <p>The stub reports itself as not native and not supported - JIDE never instantiates this
+ * class, it only uses it for {@code instanceof} comparisons against the active LAF.  Since
+ * sdrtrunk never installs this LAF, the {@code instanceof} check always returns false and
+ * JIDE proceeds to its next branch.
+ */
+public class WindowsLookAndFeel extends LookAndFeel
+{
+    @Override
+    public String getName()
+    {
+        return "Windows (stub)";
+    }
+
+    @Override
+    public String getID()
+    {
+        return "WindowsStub";
+    }
+
+    @Override
+    public String getDescription()
+    {
+        return "Compatibility stub for JIDE's instanceof checks on non-Windows JDKs.";
+    }
+
+    @Override
+    public boolean isNativeLookAndFeel()
+    {
+        return false;
+    }
+
+    @Override
+    public boolean isSupportedLookAndFeel()
+    {
+        return false;
+    }
+
+    @Override
+    public UIDefaults getDefaults()
+    {
+        return new UIDefaults();
+    }
+}

src/main/java/io/github/dsheirer/alias/AliasFactory.java

@@ -30,12 +30,16 @@ import io.github.dsheirer.alias.id.legacy.mobileID.Min;
 import io.github.dsheirer.alias.id.legacy.siteID.SiteID;
 import io.github.dsheirer.alias.id.lojack.LoJackFunctionAndID;
 import io.github.dsheirer.alias.id.priority.Priority;
+import io.github.dsheirer.alias.id.radio.NXDNTypeDRadio;
+import io.github.dsheirer.alias.id.radio.NXDNTypeDRadioRange;
 import io.github.dsheirer.alias.id.radio.P25FullyQualifiedRadio;
 import io.github.dsheirer.alias.id.radio.Radio;
 import io.github.dsheirer.alias.id.radio.RadioRange;
 import io.github.dsheirer.alias.id.record.Record;
 import io.github.dsheirer.alias.id.status.UnitStatusID;
 import io.github.dsheirer.alias.id.status.UserStatusID;
+import io.github.dsheirer.alias.id.talkgroup.NXDNTypeDTalkgroup;
+import io.github.dsheirer.alias.id.talkgroup.NXDNTypeDTalkgroupRange;
 import io.github.dsheirer.alias.id.talkgroup.P25FullyQualifiedTalkgroup;
 import io.github.dsheirer.alias.id.talkgroup.Talkgroup;
 import io.github.dsheirer.alias.id.talkgroup.TalkgroupRange;
@@ -79,6 +83,31 @@ public class AliasFactory
                 Min copyMin = new Min();
                 copyMin.setMin(originalMin.getMin());
                 return copyMin;
+            case NXDN_TYPE_D_RADIO_ID:
+                NXDNTypeDRadio originalTypeDRadio = (NXDNTypeDRadio)id;
+                NXDNTypeDRadio copyTypeDRadio = new NXDNTypeDRadio(originalTypeDRadio.getHomeRepeater(),
+                        originalTypeDRadio.getIdentifier());
+                copyTypeDRadio.setOverlap(originalTypeDRadio.overlapProperty().get());
+                return copyTypeDRadio;
+            case NXDN_TYPE_D_RADIO_ID_RANGE:
+                NXDNTypeDRadioRange originalTypeDRadioRange = (NXDNTypeDRadioRange)id;
+                NXDNTypeDRadioRange copyTypeDRadioRange = new NXDNTypeDRadioRange(originalTypeDRadioRange.getHomeRepeater(),
+                        originalTypeDRadioRange.getMinIdentifier(), originalTypeDRadioRange.getMaxIdentifier());
+                copyTypeDRadioRange.setOverlap(originalTypeDRadioRange.overlapProperty().get());
+                return copyTypeDRadioRange;
+            case NXDN_TYPE_D_TALKGROUP:
+                NXDNTypeDTalkgroup originalTypeDTalkgroup = (NXDNTypeDTalkgroup)id;
+                NXDNTypeDTalkgroup copyTypeDTalkgroup = new NXDNTypeDTalkgroup(originalTypeDTalkgroup.getHomeRepeater(),
+                        originalTypeDTalkgroup.getIdentifier());
+                copyTypeDTalkgroup.setOverlap(originalTypeDTalkgroup.overlapProperty().get());
+                return copyTypeDTalkgroup;
+            case NXDN_TYPE_D_TALKGROUP_RANGE:
+                NXDNTypeDTalkgroupRange originalTypeDTalkgroupRange = (NXDNTypeDTalkgroupRange)id;
+                NXDNTypeDTalkgroupRange copyTypeDTalkgroupRange = new NXDNTypeDTalkgroupRange(
+                        originalTypeDTalkgroupRange.getHomeRepeater(), originalTypeDTalkgroupRange.getMinIdentifier(),
+                        originalTypeDTalkgroupRange.getMaxIdentifier());
+                copyTypeDTalkgroupRange.setOverlap(originalTypeDTalkgroupRange.overlapProperty().get());
+                return copyTypeDTalkgroupRange;
             case P25_FULLY_QUALIFIED_RADIO_ID:
                 P25FullyQualifiedRadio originalP25 = (P25FullyQualifiedRadio) id;
                 P25FullyQualifiedRadio copyP25 = new P25FullyQualifiedRadio(originalP25.getWacn(),

src/main/java/io/github/dsheirer/alias/AliasList.java

@@ -47,7 +47,7 @@ import io.github.dsheirer.identifier.talkgroup.FullyQualifiedTalkgroupIdentifier
 import io.github.dsheirer.identifier.talkgroup.TalkgroupIdentifier;
 import io.github.dsheirer.identifier.tone.ToneIdentifier;
 import io.github.dsheirer.identifier.tone.ToneSequence;
-import io.github.dsheirer.module.decode.dcs.DCSCode;
+import io.github.dsheirer.module.decode.squelch.dcs.DCSCode;
 import io.github.dsheirer.protocol.Protocol;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -134,6 +134,7 @@ public class AliasList
                 switch(id.getType())
                 {
                     case TALKGROUP:
+                    case NXDN_TYPE_D_TALKGROUP:
                         Talkgroup talkgroup = (Talkgroup)id;
 
                         TalkgroupAliasList talkgroupAliasList = mTalkgroupProtocolMap.get(talkgroup.getProtocol());
@@ -147,6 +148,7 @@ public class AliasList
                         talkgroupAliasList.add(talkgroup, alias);
                         break;
                     case TALKGROUP_RANGE:
+                    case NXDN_TYPE_D_TALKGROUP_RANGE:
                         TalkgroupRange talkgroupRange = (TalkgroupRange)id;
 
                         TalkgroupAliasList talkgroupRangeAliasList = mTalkgroupProtocolMap.get(talkgroupRange.getProtocol());
@@ -186,6 +188,7 @@ public class AliasList
                         p25TalkgroupAliasList.add(qualifiedTalkgroup, alias);
                         break;
                     case RADIO_ID:
+                    case NXDN_TYPE_D_RADIO_ID:
                         Radio radio = (Radio)id;
 
                         RadioAliasList radioAliasList = mRadioProtocolMap.get(radio.getProtocol());
@@ -199,6 +202,7 @@ public class AliasList
                         radioAliasList.add(radio, alias);
                         break;
                     case RADIO_ID_RANGE:
+                    case NXDN_TYPE_D_RADIO_ID_RANGE:
                         RadioRange radioRange = (RadioRange)id;
 
                         RadioAliasList radioRangeAliasList = mRadioProtocolMap.get(radioRange.getProtocol());

src/main/java/io/github/dsheirer/alias/id/AliasID.java

@@ -35,12 +35,16 @@ import io.github.dsheirer.alias.id.legacy.talkgroup.LegacyTalkgroupID;
 import io.github.dsheirer.alias.id.legacy.uniqueID.UniqueID;
 import io.github.dsheirer.alias.id.lojack.LoJackFunctionAndID;
 import io.github.dsheirer.alias.id.priority.Priority;
+import io.github.dsheirer.alias.id.radio.NXDNTypeDRadio;
+import io.github.dsheirer.alias.id.radio.NXDNTypeDRadioRange;
 import io.github.dsheirer.alias.id.radio.P25FullyQualifiedRadio;
 import io.github.dsheirer.alias.id.radio.Radio;
 import io.github.dsheirer.alias.id.radio.RadioRange;
 import io.github.dsheirer.alias.id.record.Record;
 import io.github.dsheirer.alias.id.status.UnitStatusID;
 import io.github.dsheirer.alias.id.status.UserStatusID;
+import io.github.dsheirer.alias.id.talkgroup.NXDNTypeDTalkgroup;
+import io.github.dsheirer.alias.id.talkgroup.NXDNTypeDTalkgroupRange;
 import io.github.dsheirer.alias.id.talkgroup.P25FullyQualifiedTalkgroup;
 import io.github.dsheirer.alias.id.talkgroup.StreamAsTalkgroup;
 import io.github.dsheirer.alias.id.talkgroup.Talkgroup;
@@ -64,6 +68,10 @@ import javafx.util.Callback;
     @JsonSubTypes.Type(value = Min.class, name = "min"),
     @JsonSubTypes.Type(value = MPT1327ID.class, name = "mpt1327ID"),
     @JsonSubTypes.Type(value = NonRecordable.class, name = "nonRecordable"),
+    @JsonSubTypes.Type(value = NXDNTypeDRadio.class, name = "nxdnTypeDRadio"),
+    @JsonSubTypes.Type(value = NXDNTypeDRadioRange.class, name = "nxdnTypeDRadioRange"),
+    @JsonSubTypes.Type(value = NXDNTypeDTalkgroup.class, name = "nxdnTypeDTalkgroup"),
+    @JsonSubTypes.Type(value = NXDNTypeDTalkgroupRange.class, name = "nxdnTypeDTalkgroupRange"),
     @JsonSubTypes.Type(value = P25FullyQualifiedRadio.class, name = "p25FullyQualifiedRadio"),
     @JsonSubTypes.Type(value = P25FullyQualifiedTalkgroup.class, name = "p25FullyQualifiedTalkgroup"),
     @JsonSubTypes.Type(value = Priority.class, name = "priority"),

src/main/java/io/github/dsheirer/alias/id/AliasIDType.java

@@ -29,6 +29,10 @@ public enum AliasIDType
     LOJACK("LoJack"),
     LTR_NET_UID("LTR-Net UID"),
     MIN("Passport MIN"),
+    NXDN_TYPE_D_RADIO_ID("NXDN Type-D Radio ID"),
+    NXDN_TYPE_D_RADIO_ID_RANGE("NXDN Type-D Radio ID Range"),
+    NXDN_TYPE_D_TALKGROUP("NXDN Type-D Talkgroup"),
+    NXDN_TYPE_D_TALKGROUP_RANGE("NXDN Type-D Talkgroup Range"),
     P25_FULLY_QUALIFIED_RADIO_ID("P25 Fully Qualified Radio ID"),
     P25_FULLY_QUALIFIED_TALKGROUP("P25 Fully Qualified Talkgroup"),
     PRIORITY("Audio Priority"),
@@ -58,6 +62,7 @@ public enum AliasIDType
 
     //Values used by the View-By alias editor
     public static EnumSet<AliasIDType> VIEW_BY_VALUES = EnumSet.of(TALKGROUP, TALKGROUP_RANGE, RADIO_ID, RADIO_ID_RANGE,
+        NXDN_TYPE_D_RADIO_ID, NXDN_TYPE_D_RADIO_ID_RANGE, NXDN_TYPE_D_TALKGROUP, NXDN_TYPE_D_TALKGROUP_RANGE,
         P25_FULLY_QUALIFIED_RADIO_ID, P25_FULLY_QUALIFIED_TALKGROUP, UNIT_STATUS, STATUS, TONES);
 
     public String toString()

src/main/java/io/github/dsheirer/alias/id/INXDNTypeD.java

@@ -0,0 +1,46 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.alias.id;
+
+/**
+ * NXDN Type-D alias identifier composed of a home repeater and a radio or talkgroup identifier value.
+ */
+public interface INXDNTypeD
+{
+    /**
+     * Home repeater for the identifier
+     */
+    int getHomeRepeater();
+
+    /**
+     * Sets the home repeater for the identifier
+     */
+    void setHomeRepeater(int homeRepeater);
+
+    /**
+     * Radio or talkgroup value, without the home repeater.
+     */
+    int getIdentifier();
+
+    /**
+     * Sets the radio or talkgroup value, without the home repeater.
+     */
+    void setIdentifier(int identifier);
+}

src/main/java/io/github/dsheirer/alias/id/INXDNTypeDRange.java

@@ -0,0 +1,56 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.alias.id;
+
+/**
+ * NXDN Type-D alias identifier range of radio or talkgroup values that share a common home repeater.
+ */
+public interface INXDNTypeDRange
+{
+    /**
+     * Home repeater for the range
+     */
+    int getHomeRepeater();
+
+    /**
+     * Sets the home repeater for the range
+     */
+    void setHomeRepeater(int homeRepeater);
+
+    /**
+     * Minimum radio or talkgroup value, without the home repeater.
+     */
+    int getMinIdentifier();
+
+    /**
+     * Sets the minimum radio or talkgroup value, without the home repeater.
+     */
+    void setMinIdentifier(int identifier);
+
+    /**
+     * Maximum radio or talkgroup value, without the home repeater.
+     */
+    int getMaxIdentifier();
+
+    /**
+     * Sets the maximum radio or talkgroup value, without the home repeater.
+     */
+    void setMaxIdentifier(int identifier);
+}

src/main/java/io/github/dsheirer/alias/id/dcs/Dcs.java

@@ -22,7 +22,7 @@ package io.github.dsheirer.alias.id.dcs;
 import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlProperty;
 import io.github.dsheirer.alias.id.AliasID;
 import io.github.dsheirer.alias.id.AliasIDType;
-import io.github.dsheirer.module.decode.dcs.DCSCode;
+import io.github.dsheirer.module.decode.squelch.dcs.DCSCode;
 
 /**
  * Digital Coded Squelch (DCS) tone identifier

src/main/java/io/github/dsheirer/alias/id/radio/NXDNTypeDRadio.java

@@ -0,0 +1,96 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.alias.id.radio;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import io.github.dsheirer.alias.id.AliasIDType;
+import io.github.dsheirer.alias.id.INXDNTypeD;
+import io.github.dsheirer.preference.identifier.talkgroup.NXDNTalkgroupFormatter;
+import io.github.dsheirer.protocol.Protocol;
+
+/**
+ * NXDN Type-D radio.  The value is the over-the-air 16-bit identifier that combines the home repeater and radio so that
+ * it matches the value of an NXDN Type-D radio identifier.
+ */
+public class NXDNTypeDRadio extends Radio implements INXDNTypeD
+{
+    public NXDNTypeDRadio()
+    {
+        //No-arg JAXB constructor
+        setProtocol(Protocol.NXDN);
+    }
+
+    /**
+     * Constructs an instance
+     * @param homeRepeater for the radio
+     * @param radio value, without the home repeater
+     */
+    public NXDNTypeDRadio(int homeRepeater, int radio)
+    {
+        super(Protocol.NXDN, NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, radio));
+    }
+
+    @Override
+    public AliasIDType getType()
+    {
+        return AliasIDType.NXDN_TYPE_D_RADIO_ID;
+    }
+
+    @JsonIgnore
+    @Override
+    public int getHomeRepeater()
+    {
+        return NXDNTalkgroupFormatter.getTypeDHomeRepeater(getValue());
+    }
+
+    @Override
+    public void setHomeRepeater(int homeRepeater)
+    {
+        setValue(NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, getIdentifier()));
+    }
+
+    @JsonIgnore
+    @Override
+    public int getIdentifier()
+    {
+        return NXDNTalkgroupFormatter.getTypeDIdentifier(getValue());
+    }
+
+    @Override
+    public void setIdentifier(int identifier)
+    {
+        setValue(NXDNTalkgroupFormatter.toTypeDValue(getHomeRepeater(), identifier));
+    }
+
+    @Override
+    public String toString()
+    {
+        StringBuilder sb = new StringBuilder();
+        sb.append("Type-D Radio ID:").append(NXDNTalkgroupFormatter.toTypeD(getHomeRepeater(), getIdentifier(), true));
+        sb.append(" Protocol:").append(getProtocol());
+
+        if(!isValid())
+        {
+            sb.append(" **NOT VALID**");
+        }
+
+        return sb.toString();
+    }
+}

src/main/java/io/github/dsheirer/alias/id/radio/NXDNTypeDRadioRange.java

@@ -0,0 +1,124 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.alias.id.radio;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import io.github.dsheirer.alias.id.AliasIDType;
+import io.github.dsheirer.alias.id.INXDNTypeDRange;
+import io.github.dsheirer.preference.identifier.talkgroup.NXDNTalkgroupFormatter;
+import io.github.dsheirer.protocol.Protocol;
+
+/**
+ * NXDN Type-D radio range for a single home repeater.  The min and max values are the over-the-air 16-bit identifiers
+ * that combine the home repeater and radio.
+ */
+public class NXDNTypeDRadioRange extends RadioRange implements INXDNTypeDRange
+{
+    public NXDNTypeDRadioRange()
+    {
+        //No-arg JAXB constructor
+        setProtocol(Protocol.NXDN);
+    }
+
+    /**
+     * Constructs an instance
+     * @param homeRepeater for the range
+     * @param minRadio value, without the home repeater
+     * @param maxRadio value, without the home repeater
+     */
+    public NXDNTypeDRadioRange(int homeRepeater, int minRadio, int maxRadio)
+    {
+        super(Protocol.NXDN, NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, minRadio),
+                NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, maxRadio));
+    }
+
+    @Override
+    public AliasIDType getType()
+    {
+        return AliasIDType.NXDN_TYPE_D_RADIO_ID_RANGE;
+    }
+
+    @JsonIgnore
+    @Override
+    public int getHomeRepeater()
+    {
+        return NXDNTalkgroupFormatter.getTypeDHomeRepeater(getMinRadio());
+    }
+
+    @Override
+    public void setHomeRepeater(int homeRepeater)
+    {
+        int min = getMinIdentifier();
+        int max = getMaxIdentifier();
+        setMinRadio(NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, min));
+        setMaxRadio(NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, max));
+    }
+
+    @JsonIgnore
+    @Override
+    public int getMinIdentifier()
+    {
+        return NXDNTalkgroupFormatter.getTypeDIdentifier(getMinRadio());
+    }
+
+    @Override
+    public void setMinIdentifier(int identifier)
+    {
+        setMinRadio(NXDNTalkgroupFormatter.toTypeDValue(getHomeRepeater(), identifier));
+    }
+
+    @JsonIgnore
+    @Override
+    public int getMaxIdentifier()
+    {
+        return NXDNTalkgroupFormatter.getTypeDIdentifier(getMaxRadio());
+    }
+
+    @Override
+    public void setMaxIdentifier(int identifier)
+    {
+        setMaxRadio(NXDNTalkgroupFormatter.toTypeDValue(getHomeRepeater(), identifier));
+    }
+
+    /**
+     * Valid when the base range is valid and both ends of the range use the same home repeater.
+     */
+    @Override
+    public boolean isValid()
+    {
+        return super.isValid() && getHomeRepeater() == NXDNTalkgroupFormatter.getTypeDHomeRepeater(getMaxRadio());
+    }
+
+    @Override
+    public String toString()
+    {
+        StringBuilder sb = new StringBuilder();
+        sb.append("Type-D Radio ID Range:").append(NXDNTalkgroupFormatter.toTypeD(getHomeRepeater(), getMinIdentifier(), true));
+        sb.append(" to ").append(NXDNTalkgroupFormatter.toTypeD(getHomeRepeater(), getMaxIdentifier(), true));
+        sb.append(" Protocol:").append(getProtocol());
+
+        if(!isValid())
+        {
+            sb.append(" **NOT VALID**");
+        }
+
+        return sb.toString();
+    }
+}

src/main/java/io/github/dsheirer/alias/id/radio/RadioFormat.java

@@ -1,23 +1,20 @@
 /*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
- *  * ******************************************************************************
- *  * Copyright (C) 2014-2020 Dennis Sheirer
- *  *
- *  * This program is free software: you can redistribute it and/or modify
- *  * it under the terms of the GNU General Public License as published by
- *  * the Free Software Foundation, either version 3 of the License, or
- *  * (at your option) any later version.
- *  *
- *  * This program is distributed in the hope that it will be useful,
- *  * but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  * GNU General Public License for more details.
- *  *
- *  * You should have received a copy of the GNU General Public License
- *  * along with this program.  If not, see <http://www.gnu.org/licenses/>
- *  * *****************************************************************************
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
  */
 
 package io.github.dsheirer.alias.id.radio;
@@ -38,10 +35,11 @@ public enum RadioFormat
         "<html>APCO25 valid range is 0 to 16,777,215"),
     DMR("********", 0, 0xFFFFFF, "0 to 16,777,215",
         "<html>DMR unit id valid range is 0 to 16,777,215"),
+    NXDN("*****", 1, 0xFFFF, "1 to 65,535", "NXDN valid range is 1 to 65,535"),
     PASSPORT("********", 0, 0x7FFFFF, "0 to 8,388,607",
         "<html>PASSPORT valid range is 0 to 8,388,607"),
     UNKNOWN("********", 1, 0xFFFFFF, "1 to 16,777,215",
-        "Unknown protocol valid value range is 1-16,777,215");
+        "<html>Unknown protocol valid value range is 1-16,777,215");
 
     private String mMask;
     private int mMinimumValue;
@@ -116,6 +114,8 @@ public enum RadioFormat
                 return APCO25;
             case DMR:
                 return DMR;
+            case NXDN:
+                return NXDN;
             case PASSPORT:
                 return PASSPORT;
             default:

src/main/java/io/github/dsheirer/alias/id/radio/RadioFormatter.java

@@ -1,23 +1,20 @@
 /*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
- *  * ******************************************************************************
- *  * Copyright (C) 2014-2019 Dennis Sheirer
- *  *
- *  * This program is free software: you can redistribute it and/or modify
- *  * it under the terms of the GNU General Public License as published by
- *  * the Free Software Foundation, either version 3 of the License, or
- *  * (at your option) any later version.
- *  *
- *  * This program is distributed in the hope that it will be useful,
- *  * but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  * GNU General Public License for more details.
- *  *
- *  * You should have received a copy of the GNU General Public License
- *  * along with this program.  If not, see <http://www.gnu.org/licenses/>
- *  * *****************************************************************************
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
  */
 
 package io.github.dsheirer.alias.id.radio;
@@ -26,14 +23,14 @@ import io.github.dsheirer.preference.identifier.IntegerFormat;
 import io.github.dsheirer.preference.identifier.talkgroup.APCO25TalkgroupFormatter;
 import io.github.dsheirer.preference.identifier.talkgroup.AbstractIntegerFormatter;
 import io.github.dsheirer.preference.identifier.talkgroup.DMRTalkgroupFormatter;
+import io.github.dsheirer.preference.identifier.talkgroup.NXDNTalkgroupFormatter;
 import io.github.dsheirer.preference.identifier.talkgroup.UnknownTalkgroupFormatter;
 import io.github.dsheirer.protocol.Protocol;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import java.text.ParseException;
 import java.util.EnumMap;
 import java.util.Map;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Protocol-specific formatting of radio id values and parsing of formatted radio id values.
@@ -47,6 +44,7 @@ public class RadioFormatter
     {
         mFormatterMap.put(Protocol.APCO25, new APCO25TalkgroupFormatter());
         mFormatterMap.put(Protocol.DMR, new DMRTalkgroupFormatter());
+        mFormatterMap.put(Protocol.NXDN, new NXDNTalkgroupFormatter());
         mFormatterMap.put(Protocol.UNKNOWN, new UnknownTalkgroupFormatter());
     }
 

src/main/java/io/github/dsheirer/alias/id/talkgroup/NXDNTypeDTalkgroup.java

@@ -0,0 +1,96 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.alias.id.talkgroup;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import io.github.dsheirer.alias.id.AliasIDType;
+import io.github.dsheirer.alias.id.INXDNTypeD;
+import io.github.dsheirer.preference.identifier.talkgroup.NXDNTalkgroupFormatter;
+import io.github.dsheirer.protocol.Protocol;
+
+/**
+ * NXDN Type-D talkgroup.  The value is the over-the-air 16-bit identifier that combines the home repeater and talkgroup
+ * so that it matches the value of an NXDN Type-D talkgroup identifier.
+ */
+public class NXDNTypeDTalkgroup extends Talkgroup implements INXDNTypeD
+{
+    public NXDNTypeDTalkgroup()
+    {
+        //No-arg JAXB constructor
+        setProtocol(Protocol.NXDN);
+    }
+
+    /**
+     * Constructs an instance
+     * @param homeRepeater for the talkgroup
+     * @param talkgroup value, without the home repeater
+     */
+    public NXDNTypeDTalkgroup(int homeRepeater, int talkgroup)
+    {
+        super(Protocol.NXDN, NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, talkgroup));
+    }
+
+    @Override
+    public AliasIDType getType()
+    {
+        return AliasIDType.NXDN_TYPE_D_TALKGROUP;
+    }
+
+    @JsonIgnore
+    @Override
+    public int getHomeRepeater()
+    {
+        return NXDNTalkgroupFormatter.getTypeDHomeRepeater(getValue());
+    }
+
+    @Override
+    public void setHomeRepeater(int homeRepeater)
+    {
+        setValue(NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, getIdentifier()));
+    }
+
+    @JsonIgnore
+    @Override
+    public int getIdentifier()
+    {
+        return NXDNTalkgroupFormatter.getTypeDIdentifier(getValue());
+    }
+
+    @Override
+    public void setIdentifier(int identifier)
+    {
+        setValue(NXDNTalkgroupFormatter.toTypeDValue(getHomeRepeater(), identifier));
+    }
+
+    @Override
+    public String toString()
+    {
+        StringBuilder sb = new StringBuilder();
+        sb.append("Type-D Talkgroup:").append(NXDNTalkgroupFormatter.toTypeD(getHomeRepeater(), getIdentifier(), true));
+        sb.append(" Protocol:").append(getProtocol());
+
+        if(!isValid())
+        {
+            sb.append(" **NOT VALID**");
+        }
+
+        return sb.toString();
+    }
+}

src/main/java/io/github/dsheirer/alias/id/talkgroup/NXDNTypeDTalkgroupRange.java

@@ -0,0 +1,125 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.alias.id.talkgroup;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import io.github.dsheirer.alias.id.AliasIDType;
+import io.github.dsheirer.alias.id.INXDNTypeDRange;
+import io.github.dsheirer.preference.identifier.talkgroup.NXDNTalkgroupFormatter;
+import io.github.dsheirer.protocol.Protocol;
+
+/**
+ * NXDN Type-D talkgroup range for a single home repeater.  The min and max values are the over-the-air 16-bit
+ * identifiers that combine the home repeater and talkgroup.
+ */
+public class NXDNTypeDTalkgroupRange extends TalkgroupRange implements INXDNTypeDRange
+{
+    public NXDNTypeDTalkgroupRange()
+    {
+        //No-arg JAXB constructor
+        setProtocol(Protocol.NXDN);
+    }
+
+    /**
+     * Constructs an instance
+     * @param homeRepeater for the range
+     * @param minTalkgroup value, without the home repeater
+     * @param maxTalkgroup value, without the home repeater
+     */
+    public NXDNTypeDTalkgroupRange(int homeRepeater, int minTalkgroup, int maxTalkgroup)
+    {
+        super(Protocol.NXDN, NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, minTalkgroup),
+                NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, maxTalkgroup));
+    }
+
+    @Override
+    public AliasIDType getType()
+    {
+        return AliasIDType.NXDN_TYPE_D_TALKGROUP_RANGE;
+    }
+
+    @JsonIgnore
+    @Override
+    public int getHomeRepeater()
+    {
+        return NXDNTalkgroupFormatter.getTypeDHomeRepeater(getMinTalkgroup());
+    }
+
+    @Override
+    public void setHomeRepeater(int homeRepeater)
+    {
+        int min = getMinIdentifier();
+        int max = getMaxIdentifier();
+        setMinTalkgroup(NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, min));
+        setMaxTalkgroup(NXDNTalkgroupFormatter.toTypeDValue(homeRepeater, max));
+    }
+
+    @JsonIgnore
+    @Override
+    public int getMinIdentifier()
+    {
+        return NXDNTalkgroupFormatter.getTypeDIdentifier(getMinTalkgroup());
+    }
+
+    @Override
+    public void setMinIdentifier(int identifier)
+    {
+        setMinTalkgroup(NXDNTalkgroupFormatter.toTypeDValue(getHomeRepeater(), identifier));
+    }
+
+    @JsonIgnore
+    @Override
+    public int getMaxIdentifier()
+    {
+        return NXDNTalkgroupFormatter.getTypeDIdentifier(getMaxTalkgroup());
+    }
+
+    @Override
+    public void setMaxIdentifier(int identifier)
+    {
+        setMaxTalkgroup(NXDNTalkgroupFormatter.toTypeDValue(getHomeRepeater(), identifier));
+    }
+
+    /**
+     * Valid when the base range is valid and both ends of the range use the same home repeater.
+     */
+    @Override
+    public boolean isValid()
+    {
+        return super.isValid() &&
+                getHomeRepeater() == NXDNTalkgroupFormatter.getTypeDHomeRepeater(getMaxTalkgroup());
+    }
+
+    @Override
+    public String toString()
+    {
+        StringBuilder sb = new StringBuilder();
+        sb.append("Type-D Talkgroup Range:").append(NXDNTalkgroupFormatter.toTypeD(getHomeRepeater(), getMinIdentifier(), true));
+        sb.append(" to ").append(NXDNTalkgroupFormatter.toTypeD(getHomeRepeater(), getMaxIdentifier(), true));
+        sb.append(" Protocol:").append(getProtocol());
+
+        if(!isValid())
+        {
+            sb.append(" **NOT VALID**");
+        }
+
+        return sb.toString();
+    }
+}

src/main/java/io/github/dsheirer/alias/id/talkgroup/TalkgroupFormat.java

@@ -1,23 +1,20 @@
 /*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
- *  * ******************************************************************************
- *  * Copyright (C) 2014-2020 Dennis Sheirer
- *  *
- *  * This program is free software: you can redistribute it and/or modify
- *  * it under the terms of the GNU General Public License as published by
- *  * the Free Software Foundation, either version 3 of the License, or
- *  * (at your option) any later version.
- *  *
- *  * This program is distributed in the hope that it will be useful,
- *  * but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  * GNU General Public License for more details.
- *  *
- *  * You should have received a copy of the GNU General Public License
- *  * along with this program.  If not, see <http://www.gnu.org/licenses/>
- *  * *****************************************************************************
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
  */
 
 package io.github.dsheirer.alias.id.talkgroup;
@@ -50,6 +47,8 @@ public enum TalkgroupFormat
         "<html>MPT-1327 valid ranges are 0-127(prefix)<br>and 1-8192(ident) (ie. 000-0001 to 127-8192)"),
     NBFM("*****", 1, 0xFFFF, "1 to 65,535",
             "NBFM valid value range is 1-65,535"),
+    NXDN("*****", 0, 0xFFFF, "0 to 65,535",
+            "NXDN talkgroup valid range is 0 to 65,535"),
     PASSPORT("*****", 1, 0xFFFF, "1 to 65,535",
         "Passport valid value range is 1-65,535"),
     UNKNOWN("********", 1, 0xFFFFFF, "1 to 16,777,215",
@@ -139,6 +138,8 @@ public enum TalkgroupFormat
                 return MPT1327;
             case NBFM:
                 return NBFM;
+            case NXDN:
+                return NXDN;
             case PASSPORT:
                 return PASSPORT;
             default:

src/main/java/io/github/dsheirer/alias/id/talkgroup/TalkgroupFormatter.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2023 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -28,6 +28,7 @@ import io.github.dsheirer.preference.identifier.talkgroup.FleetsyncTalkgroupForm
 import io.github.dsheirer.preference.identifier.talkgroup.LTRTalkgroupFormatter;
 import io.github.dsheirer.preference.identifier.talkgroup.MDC1200TalkgroupFormatter;
 import io.github.dsheirer.preference.identifier.talkgroup.MPT1327TalkgroupFormatter;
+import io.github.dsheirer.preference.identifier.talkgroup.NXDNTalkgroupFormatter;
 import io.github.dsheirer.preference.identifier.talkgroup.PassportTalkgroupFormatter;
 import io.github.dsheirer.preference.identifier.talkgroup.UnknownTalkgroupFormatter;
 import io.github.dsheirer.protocol.Protocol;
@@ -59,6 +60,7 @@ public class TalkgroupFormatter
         mFormatterMap.put(Protocol.LTR_NET, ltr);
         mFormatterMap.put(Protocol.MDC1200, new MDC1200TalkgroupFormatter());
         mFormatterMap.put(Protocol.MPT1327, new MPT1327TalkgroupFormatter());
+        mFormatterMap.put(Protocol.NXDN, new NXDNTalkgroupFormatter());
         mFormatterMap.put(Protocol.PASSPORT, new PassportTalkgroupFormatter());
         mFormatterMap.put(Protocol.UNKNOWN, new UnknownTalkgroupFormatter());
     }

src/main/java/io/github/dsheirer/audio/AbstractAudioFilter.java

@@ -0,0 +1,17 @@
+package io.github.dsheirer.audio;
+
+/**
+ * Used for defining an array list of filter methods to be implemented in AudioModule
+ * The filters will be applied in the order given in the list.
+ * Each audio filter mush implement the filter method.
+ */
+
+public abstract class AbstractAudioFilter
+{
+    /**
+     * To be overridden by each audio filter
+     * @param audio a buffer of 8 KHz audio samples
+     * @return float[] filtered buffer of 8 KHz audio samples
+     */
+    public abstract float[] filter(float[] audio);
+}

src/main/java/io/github/dsheirer/audio/AudioGainFilter.java

@@ -0,0 +1,44 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.audio;
+
+import io.github.dsheirer.dsp.gain.AudioGainAndDcFilter;
+
+/**
+ * This is a wrapper for the AudioGainAndDcFilter class so it can be used with the AudioModule filter list.
+ * Usually instantiated in the DecoderFactory
+ */
+public class AudioGainFilter extends AbstractAudioFilter
+{
+    AudioGainAndDcFilter mAudioGain;
+
+    public AudioGainFilter(float minGain, float maxGain, float objectiveAmplitude)
+    {
+        mAudioGain = new AudioGainAndDcFilter(minGain, maxGain, objectiveAmplitude);
+        mAudioGain.setDecayRate(2);     // to remove pumping effect
+        mAudioGain.reset();
+    }
+
+    @Override
+    public float[] filter(float[] audio)
+    {
+        return mAudioGain.process(audio);
+    }
+}

src/main/java/io/github/dsheirer/audio/AudioModule.java

@@ -32,6 +32,8 @@ import io.github.dsheirer.sample.real.IRealBufferListener;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.List;
+
 /**
  * Provides packaging of demodulated audio sample buffers into audio segments for broadcast to registered listeners.
  * Includes audio packet metadata in constructed audio segments.
@@ -42,36 +44,7 @@ public class AudioModule extends AbstractAudioModule implements ISquelchStateLis
     Listener<float[]>
 {
     private static final Logger mLog = LoggerFactory.getLogger(AudioModule.class);
-    private static float[] sHighPassFilterCoefficients;
-    private final boolean mAudioFilterEnable;
-
-    static
-    {
-        FIRFilterSpecification specification = FIRFilterSpecification.highPassBuilder()
-            .sampleRate(8000)
-            .stopBandCutoff(200)
-            .stopBandAmplitude(0.0)
-            .stopBandRipple(0.025)
-            .passBandStart(300)
-            .passBandAmplitude(1.0)
-            .passBandRipple(0.01)
-            .build();
-        try
-        {
-            RemezFIRFilterDesigner designer = new RemezFIRFilterDesigner(specification);
-
-            if(designer.isValid())
-            {
-                sHighPassFilterCoefficients = designer.getImpulseResponse();
-            }
-        }
-        catch(FilterDesignException fde)
-        {
-            mLog.error("Filter design error", fde);
-        }
-    }
-
-    private final IRealFilter mHighPassFilter = FilterFactory.getRealFilter(sHighPassFilterCoefficients);
+    private List<AbstractAudioFilter>mAudioFilters;
     private final SquelchStateListener mSquelchStateListener = new SquelchStateListener();
     private SquelchState mSquelchState = SquelchState.SQUELCH;
 
@@ -81,23 +54,23 @@ public class AudioModule extends AbstractAudioModule implements ISquelchStateLis
      * @param aliasList for aliasing identifiers
      * @param timeslot for this audio module
      * @param maxAudioSegmentLength in milliseconds
-     * @param audioFilterEnable to enable or disable high-pass audio filter
+     * @param audioFilters a list of audio filters to apply to the incoming audio samples
      */
-    public AudioModule(AliasList aliasList, int timeslot, long maxAudioSegmentLength, boolean audioFilterEnable)
+    public AudioModule(AliasList aliasList, int timeslot, long maxAudioSegmentLength, List<AbstractAudioFilter> audioFilters)
     {
         super(aliasList, timeslot, maxAudioSegmentLength);
-        mAudioFilterEnable = audioFilterEnable;
+        mAudioFilters = audioFilters;
     }
 
     /**
      * Creates an Audio Module.
      * @param aliasList for aliasing identifiers
-     * @param audioFilterEnable to enable or disable high-pass audio filter
+     * @param audioFilters a list of audio filters to apply to the incoming audio samples
      */
-    public AudioModule(AliasList aliasList, boolean audioFilterEnable)
+    public AudioModule(AliasList aliasList,  List<AbstractAudioFilter> audioFilters)
     {
         super(aliasList);
-        mAudioFilterEnable = audioFilterEnable;
+        mAudioFilters = audioFilters;
     }
 
     @Override
@@ -128,9 +101,13 @@ public class AudioModule extends AbstractAudioModule implements ISquelchStateLis
     {
         if(mSquelchState == SquelchState.UNSQUELCH)
         {
-            if(mAudioFilterEnable)
+            // apply audio filters if any (i.e. deemphasis, high pass, etc.)
+            if(!mAudioFilters.isEmpty())
             {
-                audioBuffer = mHighPassFilter.filter(audioBuffer);
+                for(AbstractAudioFilter filter : mAudioFilters)
+                {
+                    audioBuffer = filter.filter(audioBuffer);
+                }
             }
 
             addAudio(audioBuffer);

src/main/java/io/github/dsheirer/audio/AudioSegment.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2024 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -61,7 +61,7 @@ import org.slf4j.LoggerFactory;
  *
  * Producers will add audio buffers and update identifiers throughout the life-cycle of an audio segment.  The producer
  * will signal the completion of an audio segment by setting the complete property to true.  This allows consumers the
- * option to process the audio buffers throughout the life-cycle of the segment, or to process all of the buffers once
+ * option to process the audio buffers throughout the life-cycle of the segment, or to process all the buffers once
  * the segment is complete.
  */
 public class AudioSegment implements Listener<IdentifierUpdateNotification>

src/main/java/io/github/dsheirer/audio/HighPassAudioFilter.java

@@ -0,0 +1,50 @@
+package io.github.dsheirer.audio;
+
+import io.github.dsheirer.dsp.filter.FilterFactory;
+import io.github.dsheirer.dsp.filter.design.FilterDesignException;
+import io.github.dsheirer.dsp.filter.fir.FIRFilterSpecification;
+import io.github.dsheirer.dsp.filter.fir.real.IRealFilter;
+import io.github.dsheirer.dsp.filter.fir.remez.RemezFIRFilterDesigner;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class HighPassAudioFilter extends AbstractAudioFilter
+{
+    private static final Logger mLog = LoggerFactory.getLogger(HighPassAudioFilter.class);
+    private static float[] sHighPassFilterCoefficients;
+
+    static
+    {
+        FIRFilterSpecification specification = FIRFilterSpecification.highPassBuilder()
+                .sampleRate(8000)
+                .stopBandCutoff(200)
+                .stopBandAmplitude(0.0)
+                .stopBandRipple(0.025)
+                .passBandStart(300)
+                .passBandAmplitude(1.0)
+                .passBandRipple(0.01)
+                .build();
+        try
+        {
+            RemezFIRFilterDesigner designer = new RemezFIRFilterDesigner(specification);
+
+            if(designer.isValid())
+            {
+                sHighPassFilterCoefficients = designer.getImpulseResponse();
+            }
+        }
+        catch(FilterDesignException fde)
+        {
+            mLog.error("Filter design error", fde);
+        }
+    }
+
+    private final IRealFilter mHighPassFilter = FilterFactory.getRealFilter(sHighPassFilterCoefficients);
+
+    @Override
+    public float[] filter(float[] audio)
+    {
+        audio = mHighPassFilter.filter(audio);
+        return audio;
+    }
+}

src/main/java/io/github/dsheirer/audio/IAudioController.java

@@ -1,9 +1,27 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
 package io.github.dsheirer.audio;
 
-import io.github.dsheirer.audio.playback.AudioOutput;
+import io.github.dsheirer.audio.playback.AudioChannel;
+import io.github.dsheirer.audio.playback.AudioPlaybackDeviceDescriptor;
 import io.github.dsheirer.sample.Listener;
-import io.github.dsheirer.source.mixer.MixerChannelConfiguration;
-
 import java.util.List;
 
 /**
@@ -12,13 +30,13 @@ import java.util.List;
 public interface IAudioController
 {
 	/* Current Mixer and MixerChannel configuration */
-	public void setMixerChannelConfiguration( MixerChannelConfiguration entry ) throws AudioException;
-	public MixerChannelConfiguration getMixerChannelConfiguration() throws AudioException;
+	public void setAudioPlaybackDevice(AudioPlaybackDeviceDescriptor device ) throws AudioException;
+	public AudioPlaybackDeviceDescriptor getAudioPlaybackDevice() throws AudioException;
 	
-	/* Audio Output(s) */
-	public List<AudioOutput> getAudioOutputs();
+	/* Audio Channel(s) */
+	public List<AudioChannel> getAudioChannels();
 
 	/* Controller Audio Event Listener */
-	public void addControllerListener( Listener<AudioEvent> listener );
-	public void removeControllerListener( Listener<AudioEvent> listener );
+	public void addAudioEventListener(Listener<AudioEvent> listener );
+	public void removeAudioEventListener(Listener<AudioEvent> listener );
 }

src/main/java/io/github/dsheirer/audio/broadcast/AbstractAudioBroadcaster.java

@@ -36,6 +36,7 @@ public abstract class AbstractAudioBroadcaster<T extends BroadcastConfiguration>
     protected ObjectProperty<BroadcastState> mBroadcastState = new SimpleObjectProperty<>(BroadcastState.READY);
     protected ObjectProperty<BroadcastState> mLastBadBroadcastState = new SimpleObjectProperty<>();
     protected int mStreamedAudioCount = 0;
+    protected int mDuplicateRejectedAudioCount = 0;
     protected int mErrorAudioCount = 0;
     protected int mAgedOffAudioCount = 0;
 
@@ -163,6 +164,22 @@ public abstract class AbstractAudioBroadcaster<T extends BroadcastConfiguration>
         mStreamedAudioCount++;
     }
 
+    /**
+     * Number of audio recordings rejected by the remote service as duplicates.
+     */
+    public int getDuplicateRejectedAudioCount()
+    {
+        return mDuplicateRejectedAudioCount;
+    }
+
+    /**
+     * Increments the duplicate-rejected audio count by one.
+     */
+    public void incrementDuplicateRejectedAudioCount()
+    {
+        mDuplicateRejectedAudioCount++;
+    }
+
     /**
      * Number of audio recordings that were removed for exceeding age limit
      */

src/main/java/io/github/dsheirer/audio/broadcast/BroadcastEvent.java

@@ -82,6 +82,7 @@ public class BroadcastEvent
         BROADCASTER_QUEUE_CHANGE,
         BROADCASTER_STATE_CHANGE,
         BROADCASTER_STREAMED_COUNT_CHANGE,
+        BROADCASTER_DUPLICATE_REJECTED_COUNT_CHANGE,
         BROADCASTER_AGED_OFF_COUNT_CHANGE,
         BROADCASTER_ERROR_COUNT_CHANGE,
         BROADCASTER_DELETE,

src/main/java/io/github/dsheirer/audio/broadcast/BroadcastModel.java

@@ -62,11 +62,12 @@ public class BroadcastModel extends AbstractTableModel implements Listener<Audio
     public static final int COLUMN_BROADCASTER_STATUS = 2;
     public static final int COLUMN_BROADCASTER_QUEUE_SIZE = 3;
     public static final int COLUMN_BROADCASTER_STREAMED_COUNT = 4;
-    public static final int COLUMN_BROADCASTER_AGED_OFF_COUNT = 5;
-    public static final int COLUMN_BROADCASTER_ERROR_COUNT = 6;
+    public static final int COLUMN_BROADCASTER_DUPLICATE_REJECTED_COUNT = 5;
+    public static final int COLUMN_BROADCASTER_AGED_OFF_COUNT = 6;
+    public static final int COLUMN_BROADCASTER_ERROR_COUNT = 7;
 
     public static final String[] COLUMN_NAMES = new String[]
-        {"Stream Type", "Name", "Status", "Queued", "Streamed/Uploaded", "Aged Off", "Upload Error"};
+        {"Stream Type", "Name", "Status", "Queued", "Streamed/Uploaded", "Duplicate Rejected", "Aged Off", "Upload Error"};
 
     private ObservableList<ConfiguredBroadcast> mConfiguredBroadcasts =
         FXCollections.observableArrayList(ConfiguredBroadcast.extractor());
@@ -361,7 +362,7 @@ public class BroadcastModel extends AbstractTableModel implements Listener<Audio
                 }
 
                 broadcast(new BroadcastEvent(audioBroadcaster, BroadcastEvent.Event.BROADCASTER_ADD));
-                ThreadPool.CACHED.submit(audioBroadcaster::start);
+                ThreadPool.CACHED.submit(() -> audioBroadcaster.start());
             }
         }
     }
@@ -531,6 +532,12 @@ public class BroadcastModel extends AbstractTableModel implements Listener<Audio
                         fireTableCellUpdated(row, COLUMN_BROADCASTER_STREAMED_COUNT);
                     }
                     break;
+                case BROADCASTER_DUPLICATE_REJECTED_COUNT_CHANGE:
+                    if(row >= 0)
+                    {
+                        fireTableCellUpdated(row, COLUMN_BROADCASTER_DUPLICATE_REJECTED_COUNT);
+                    }
+                    break;
                 case BROADCASTER_AGED_OFF_COUNT_CHANGE:
                     if(row >= 0)
                     {
@@ -607,6 +614,12 @@ public class BroadcastModel extends AbstractTableModel implements Listener<Audio
                                 return configuredBroadcast.getAudioBroadcaster().getStreamedAudioCount();
                             }
                             break;
+                        case COLUMN_BROADCASTER_DUPLICATE_REJECTED_COUNT:
+                            if(configuredBroadcast.hasAudioBroadcaster())
+                            {
+                                return configuredBroadcast.getAudioBroadcaster().getDuplicateRejectedAudioCount();
+                            }
+                            break;
                         case COLUMN_BROADCASTER_AGED_OFF_COUNT:
                             if(configuredBroadcast.hasAudioBroadcaster())
                             {
@@ -643,6 +656,7 @@ public class BroadcastModel extends AbstractTableModel implements Listener<Audio
             case COLUMN_BROADCASTER_AGED_OFF_COUNT:
             case COLUMN_BROADCASTER_QUEUE_SIZE:
             case COLUMN_BROADCASTER_STREAMED_COUNT:
+            case COLUMN_BROADCASTER_DUPLICATE_REJECTED_COUNT:
             case COLUMN_BROADCASTER_ERROR_COUNT:
                 return Integer.class;
             case COLUMN_BROADCAST_SERVER_TYPE:

src/main/java/io/github/dsheirer/audio/broadcast/BroadcastStatusPanel.java

@@ -151,7 +151,10 @@ public class BroadcastStatusPanel extends JPanel
                     else if(state == BroadcastState.DISABLED)
                     {
                         setBackground(table.getBackground());
-                        setForeground(Color.LIGHT_GRAY);
+                        //Use the LAF's disabled-foreground so the cell reads correctly on any
+                        //theme - LIGHT_GRAY is invisible on a light background.
+                        Color disabled = javax.swing.UIManager.getColor("Label.disabledForeground");
+                        setForeground(disabled != null ? disabled : table.getForeground());
                     }
                     else if(state == BroadcastState.INVALID_SETTINGS ||
                             state == BroadcastState.NETWORK_UNAVAILABLE)

src/main/java/io/github/dsheirer/audio/broadcast/broadcastify/BroadcastifyCallBroadcaster.java

@@ -34,6 +34,7 @@ import io.github.dsheirer.identifier.Form;
 import io.github.dsheirer.identifier.Identifier;
 import io.github.dsheirer.identifier.IdentifierClass;
 import io.github.dsheirer.identifier.Role;
+import io.github.dsheirer.identifier.alias.TalkerAliasIdentifier;
 import io.github.dsheirer.identifier.configuration.AliasListConfigurationIdentifier;
 import io.github.dsheirer.identifier.configuration.ConfigurationLongIdentifier;
 import io.github.dsheirer.identifier.patch.PatchGroup;
@@ -253,6 +254,8 @@ public class BroadcastifyCallBroadcaster extends AbstractAudioBroadcaster<Broadc
                 String radioId = getFrom(audioRecording);
                 float frequency = getFrequency(audioRecording);
 
+                String radioIdAlias = getFromAlias(audioRecording);
+
                 BroadcastifyCallBuilder bodyBuilder = new BroadcastifyCallBuilder();
                 bodyBuilder.addPart(FormField.API_KEY, getBroadcastConfiguration().getApiKey())
                     .addPart(FormField.SYSTEM_ID, getBroadcastConfiguration().getSystemID())
@@ -263,6 +266,11 @@ public class BroadcastifyCallBroadcaster extends AbstractAudioBroadcaster<Broadc
                     .addPart(FormField.FREQUENCY, frequency)
                     .addPart(FormField.ENCODING, ENCODING_TYPE_MP3);
 
+                if(radioIdAlias != null && !radioIdAlias.isEmpty())
+                {
+                    bodyBuilder.addPart(FormField.RADIO_ID_ALIAS, radioIdAlias);
+                }
+
                 try
                 {
                     HttpRequest request = HttpRequest.newBuilder()
@@ -362,6 +370,9 @@ public class BroadcastifyCallBroadcaster extends AbstractAudioBroadcaster<Broadc
                                 else if(urlResponse.startsWith("1 SKIPPED"))
                                 {
                                     //Broadcastify is telling us to skip audio upload - someone already uploaded it
+                                    incrementDuplicateRejectedAudioCount();
+                                    broadcast(new BroadcastEvent(BroadcastifyCallBroadcaster.this,
+                                        BroadcastEvent.Event.BROADCASTER_DUPLICATE_REJECTED_COUNT_CHANGE));
                                     audioRecording.removePendingReplay();
                                 }
                                 else
@@ -446,6 +457,27 @@ public class BroadcastifyCallBroadcaster extends AbstractAudioBroadcaster<Broadc
         return "0";
     }
 
+    /**
+     * Resolves the over-the-air talker alias for the FROM (source radio) identifier, acquired in real-time from RF
+     * (e.g. P25 Motorola Talker Alias or DMR Talker Alias). Returns null if no OTA alias was received for this call.
+     * This is sent as the srcId_alias field in Broadcastify uploads.
+     */
+    private static String getFromAlias(AudioRecording audioRecording)
+    {
+        for(Identifier identifier: audioRecording.getIdentifierCollection().getIdentifiers(Role.FROM))
+        {
+            if(identifier instanceof TalkerAliasIdentifier talkerAliasIdentifier)
+            {
+                if(talkerAliasIdentifier.isValid())
+                {
+                    return talkerAliasIdentifier.getValue();
+                }
+            }
+        }
+
+        return null;
+    }
+
     /**
      * Creates a formatted string with the TO identifiers or uses a default of zero (0)
      */

src/main/java/io/github/dsheirer/audio/broadcast/broadcastify/FormField.java

@@ -30,6 +30,7 @@ public enum FormField
     TIMESTAMP("ts"),
     TALKGROUP_ID("tg"),
     RADIO_ID("src"),
+    RADIO_ID_ALIAS("srcId_alias"),
     FREQUENCY("freq"),
     ENCODING("enc"),
     TEST("test");

src/main/java/io/github/dsheirer/audio/broadcast/icecast/IcecastHTTPAudioBroadcaster.java

@@ -55,6 +55,7 @@ public class IcecastHTTPAudioBroadcaster extends IcecastAudioBroadcaster
     private static final long CONNECTION_ATTEMPT_TIMEOUT_MILLISECONDS = 5000; // 5 seconds
     private static final long RECONNECT_INTERVAL_MILLISECONDS = 30000; //30 seconds
     private static final String HTTP_1_0_OK_HEX_DUMP = "48 54 54 50 2F 31 2E 30 20 32 30 30 20 4F 4B";
+    private static final String HTTP_1_1_CONTINUE_HEX_DUMP = "48 54 54 50 2F 31 2E 31 20 31 30 30";
 
     private NioSocketConnector mSocketConnector;
     private IoSession mStreamingSession = null;
@@ -262,6 +263,7 @@ public class IcecastHTTPAudioBroadcaster extends IcecastAudioBroadcaster
             {
                 mHTTPHeaders = new HashMap<>();
                 mHTTPHeaders.put(IcecastHeader.ACCEPT.getValue(), "*/*");
+                mHTTPHeaders.put(IcecastHeader.EXPECT.getValue(), "100-continue");
                 mHTTPHeaders.put(IcecastHeader.CONTENT_TYPE.getValue(), getConfiguration().getBroadcastFormat().getValue());
                 mHTTPHeaders.put(IcecastHeader.USER_AGENT.getValue(), SystemProperties.getInstance().getApplicationName());
                 mHTTPHeaders.put(IcecastHeader.AUTHORIZATION.getValue(), getConfiguration().getBase64EncodedCredentials());
@@ -350,7 +352,7 @@ public class IcecastHTTPAudioBroadcaster extends IcecastAudioBroadcaster
                 {
                     String hexDump = ((ProtocolDecoderException)throwable).getHexdump();
 
-                    if(hexDump.startsWith(HTTP_1_0_OK_HEX_DUMP))
+                    if(hexDump.startsWith(HTTP_1_0_OK_HEX_DUMP) || hexDump.startsWith(HTTP_1_1_CONTINUE_HEX_DUMP))
                     {
                         setBroadcastState(BroadcastState.CONNECTED);
 						mConnectionFailureLogged.set(false);
@@ -432,6 +434,10 @@ public class IcecastHTTPAudioBroadcaster extends IcecastAudioBroadcaster
                 switch(response.getStatus())
                 {
                     case INFORMATIONAL_CONTINUE:
+                        //Icecast 2.5+ signals that we can start sending audio with 100-continue
+                        setBroadcastState(BroadcastState.CONNECTED);
+                        mConnecting.set(false);
+                        mConnectionFailureLogged.set(false);
                         break;
                     case SUCCESS_OK:
                         setBroadcastState(BroadcastState.CONNECTED);
@@ -500,7 +506,8 @@ public class IcecastHTTPAudioBroadcaster extends IcecastAudioBroadcaster
 
             mMessage = new String(bytes);
 
-            Pattern pattern = Pattern.compile("HTTP/1.0 (\\d{3})");
+            //Icecast 2.4+ responds with HTTP/1.0 and Icecast 2.5+ responds with HTTP/1.1
+            Pattern pattern = Pattern.compile("HTTP/1\\.[01] (\\d{3})");
             Matcher m = pattern.matcher(mMessage);
 
             if(m.find())

src/main/java/io/github/dsheirer/audio/broadcast/openmhz/OpenMHzEditor.java

@@ -17,13 +17,14 @@
  * ****************************************************************************
  */
 
- package io.github.dsheirer.gui.playlist.streaming;
+ package io.github.dsheirer.audio.broadcast.openmhz;
 
  import io.github.dsheirer.audio.broadcast.BroadcastServerType;
  import io.github.dsheirer.audio.broadcast.openmhz.OpenMHzBroadcaster;
  import io.github.dsheirer.audio.broadcast.openmhz.OpenMHzConfiguration;
  import io.github.dsheirer.gui.control.IntegerTextField;
- import io.github.dsheirer.playlist.PlaylistManager;
+import io.github.dsheirer.gui.playlist.streaming.AbstractBroadcastEditor;
+import io.github.dsheirer.playlist.PlaylistManager;
  import javafx.geometry.HPos;
  import javafx.geometry.Insets;
  import javafx.scene.control.Alert;

src/main/java/io/github/dsheirer/audio/codec/mbe/JmbeAudioModule.java

@@ -35,9 +35,12 @@ import java.net.URL;
 import java.net.URLClassLoader;
 import java.nio.file.Path;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import jmbe.iface.IAudioCodec;
 import jmbe.iface.IAudioCodecLibrary;
+import jmbe.iface.IAudioCodecLibraryV2;
+import jmbe.iface.IAudioCodecV2;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -47,7 +50,7 @@ import org.slf4j.LoggerFactory;
 public abstract class JmbeAudioModule extends AbstractAudioModule implements Listener<IMessage>, IMessageListener,
     ISquelchStateListener
 {
-    private static final Logger mLog = LoggerFactory.getLogger(JmbeAudioModule.class);
+    private static final Logger LOG = LoggerFactory.getLogger(JmbeAudioModule.class);
     private static final String JMBE_AUDIO_LIBRARY = "JMBE";
     private static final List<String> mLibraryLoadStatusLogged = new ArrayList<>();
     private IAudioCodec mAudioCodec;
@@ -62,6 +65,37 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
         loadConverter();
     }
 
+    /**
+     * List of features supported by the JMBE audio library.  Note: features are only supported in Version 2.0+
+     * @return list of features or an empty list if the current library version doesn't support features.
+     */
+    public List<String> getFeatures()
+    {
+        if(mAudioCodec instanceof IAudioCodecV2 v2)
+        {
+            return v2.getFeatures();
+        }
+
+        return Collections.emptyList();
+    }
+
+    /**
+     * Sets the JMBE feature
+     * @param name of the feature
+     * @param value for the feature
+     */
+    public void setFeature(String name, Object value)
+    {
+        if(mAudioCodec instanceof IAudioCodecV2 v2)
+        {
+            v2.setFeature(name, value);
+        }
+        else
+        {
+            LOG.info("Feature [" + name + "] is not supported by the current JMBE audio codec library version");
+        }
+    }
+
     @Override
     protected void closeAudioSegment()
     {
@@ -135,7 +169,7 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
             {
                 if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
                 {
-                    mLog.info("Loading JMBE library from [" + path + "]");
+                    LOG.info("Loading JMBE library from [" + path + "]");
                 }
 
                 try
@@ -143,13 +177,32 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
                     URLClassLoader childClassLoader = new URLClassLoader(new URL[]{path.toUri().toURL()},
                             this.getClass().getClassLoader());
 
-                    sLoadedJmbeAudioConverterClass = Class.forName("jmbe.JMBEAudioLibrary", true, childClassLoader);
+                    try
+                    {
+                        sLoadedJmbeAudioConverterClass = Class.forName("jmbe.JMBEAudioLibraryV2", true, childClassLoader);
+                    }
+                    catch(ClassNotFoundException legacyLibrary)
+                    {
+                        try
+                        {
+                            sLoadedJmbeAudioConverterClass = Class.forName("jmbe.JMBEAudioLibrary", true, childClassLoader);
+                        }
+                        catch(ClassNotFoundException missingLibrary)
+                        {
+                            if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
+                            {
+                                LOG.error("Couldn't load JMBE audio conversion library from [" + path +
+                                    "] - neither V2 nor V1 library class was found");
+                                mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
+                            }
+                        }
+                    }
                 }
                 catch(IllegalArgumentException iae)
                 {
                     if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY + getCodecName()))
                     {
-                        mLog.error("Couldn't load JMBE audio conversion library - " + iae.getMessage());
+                        LOG.error("Couldn't load JMBE audio conversion library - " + iae.getMessage());
                         mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY + getCodecName());
                     }
                 }
@@ -157,18 +210,11 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
                 {
                     if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
                     {
-                        mLog.error("Couldn't load JMBE audio conversion library from path [" + path + "]");
-                        mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
-                    }
-                }
-                catch(ClassNotFoundException e1)
-                {
-                    if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
-                    {
-                        mLog.error("Couldn't load JMBE audio conversion library - class not found");
+                        LOG.error("Couldn't load JMBE audio conversion library from path [" + path + "]");
                         mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
                     }
                 }
+
             }
         }
 
@@ -183,11 +229,23 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
                     if((library.getMajorVersion() == 1 && library.getMinorVersion() >= 0 &&
                             library.getBuildVersion() >= 0) || library.getMajorVersion() >= 1)
                     {
-                        audioConverter = library.getAudioConverter(getCodecName());
+                        audioConverter = library instanceof IAudioCodecLibraryV2 libraryV2 ?
+                            libraryV2.getAudioConverterV2(getCodecName()) :
+                            library.getAudioConverter(getCodecName());
+
+                        String codecStatusKey = JMBE_AUDIO_LIBRARY + ":codec:" + getCodecName();
+                        if(!mLibraryLoadStatusLogged.contains(codecStatusKey))
+                        {
+                            LOG.info("JMBE codec [" + getCodecName() + "] class [" +
+                                audioConverter.getClass().getName() + "] features [" +
+                                (audioConverter instanceof IAudioCodecV2 v2 ?
+                                    v2.getFeatures() : Collections.emptyList()) + "]");
+                            mLibraryLoadStatusLogged.add(codecStatusKey);
+                        }
 
                         if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
                         {
-                            mLog.info("JMBE audio conversion library loaded: " + library.getVersion());
+                            LOG.info("JMBE audio conversion library loaded: " + library.getVersion());
                             mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
                         }
                     }
@@ -195,7 +253,7 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
                     {
                         if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
                         {
-                            mLog.warn("JMBE library version 1.0.0 or higher is required - found: " + library.getVersion());
+                            LOG.warn("JMBE library version 1.0.0 or higher is required - found: " + library.getVersion());
                             mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
                         }
                     }
@@ -204,7 +262,7 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
                 {
                     if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
                     {
-                        mLog.info("JMBE audio conversion library NOT FOUND");
+                        LOG.info("JMBE audio conversion library NOT FOUND");
                         mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
                     }
                 }
@@ -213,7 +271,7 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
             {
                 if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
                 {
-                    mLog.error("Couldn't load JMBE audio conversion library - invocation target exception", ite);
+                    LOG.error("Couldn't load JMBE audio conversion library - invocation target exception", ite);
                     mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
                 }
             }
@@ -221,7 +279,7 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
             {
                 if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
                 {
-                    mLog.error("Couldn't load JMBE audio conversion library - instantiation exception", e1);
+                    LOG.error("Couldn't load JMBE audio conversion library - instantiation exception", e1);
                     mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
                 }
             }
@@ -229,7 +287,7 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
             {
                 if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
                 {
-                    mLog.error("Couldn't load JMBE audio conversion library - security restrictions");
+                    LOG.error("Couldn't load JMBE audio conversion library - security restrictions");
                     mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
                 }
             }
@@ -237,7 +295,7 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
             {
                 if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
                 {
-                    mLog.error("Couldn't load JMBE audio conversion library - no such method exception");
+                    LOG.error("Couldn't load JMBE audio conversion library - no such method exception");
                     mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
                 }
             }
@@ -246,7 +304,7 @@ public abstract class JmbeAudioModule extends AbstractAudioModule implements Lis
         {
             if(!mLibraryLoadStatusLogged.contains(JMBE_AUDIO_LIBRARY))
             {
-                mLog.warn("JMBE audio library path is NOT SET in your User Preferences.");
+                LOG.warn("JMBE audio library path is NOT SET in your User Preferences.");
                 mLibraryLoadStatusLogged.add(JMBE_AUDIO_LIBRARY);
             }
         }

src/main/java/io/github/dsheirer/audio/codec/mbe/MBECallSequence.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -26,7 +26,6 @@ import com.fasterxml.jackson.annotation.JsonPropertyOrder;
 import com.fasterxml.jackson.annotation.JsonRootName;
 import io.github.dsheirer.identifier.Identifier;
 import io.github.dsheirer.identifier.encryption.EncryptionKey;
-import io.github.dsheirer.module.decode.p25.audio.VoiceFrame;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -288,10 +287,18 @@ public class MBECallSequence
         }
         else
         {
-            mVoiceFrames.add(new VoiceFrame(timestamp, frame));
+            add(new VoiceFrame(timestamp, frame));
         }
     }
 
+    /**
+     * Adds the voice frame to the sequence
+     */
+    public void add(VoiceFrame voiceFrame)
+    {
+        mVoiceFrames.add(voiceFrame);
+    }
+
     /**
      * Adds an encrypted audio frame to this call sequence
      *
@@ -317,6 +324,6 @@ public class MBECallSequence
      */
     public void addEncryptedVoiceFrame(long timestamp, String frame, int algorithm, int keyid, String messageIndicator)
     {
-        mVoiceFrames.add(new VoiceFrame(timestamp, frame, algorithm, keyid, messageIndicator));
+        add(new VoiceFrame(timestamp, frame, algorithm, keyid, messageIndicator));
     }
 }

src/main/java/io/github/dsheirer/audio/codec/mbe/MBECallSequenceConverter.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2023 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -25,7 +25,6 @@ import io.github.dsheirer.audio.AudioSegment;
 import io.github.dsheirer.identifier.IdentifierUpdateNotification;
 import io.github.dsheirer.module.decode.p25.audio.P25P1AudioModule;
 import io.github.dsheirer.module.decode.p25.audio.P25P1CallSequenceRecorder;
-import io.github.dsheirer.module.decode.p25.audio.VoiceFrame;
 import io.github.dsheirer.module.decode.p25.identifier.radio.APCO25RadioIdentifier;
 import io.github.dsheirer.module.decode.p25.identifier.talkgroup.APCO25Talkgroup;
 import io.github.dsheirer.preference.UserPreferences;

src/main/java/io/github/dsheirer/audio/codec/mbe/MBECallSequenceReader.java

@@ -1,23 +1,20 @@
 /*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
- *  * ******************************************************************************
- *  * Copyright (C) 2014-2019 Dennis Sheirer
- *  *
- *  * This program is free software: you can redistribute it and/or modify
- *  * it under the terms of the GNU General Public License as published by
- *  * the Free Software Foundation, either version 3 of the License, or
- *  * (at your option) any later version.
- *  *
- *  * This program is distributed in the hope that it will be useful,
- *  * but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  * GNU General Public License for more details.
- *  *
- *  * You should have received a copy of the GNU General Public License
- *  * along with this program.  If not, see <http://www.gnu.org/licenses/>
- *  * *****************************************************************************
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
  */
 
 package io.github.dsheirer.audio.codec.mbe;
@@ -25,7 +22,6 @@ package io.github.dsheirer.audio.codec.mbe;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.base.Joiner;
-import io.github.dsheirer.module.decode.p25.audio.VoiceFrame;
 
 import java.io.IOException;
 import java.nio.file.Files;

src/main/java/io/github/dsheirer/audio/codec/mbe/VoiceFrame.java

@@ -1,20 +1,23 @@
-/*******************************************************************************
- * sdr-trunk
- * Copyright (C) 2014-2019 Dennis Sheirer
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
- * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public
- * License as published by  the Free Software Foundation, either version 3 of the License, or  (at your option) any
- * later version.
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful,  but WITHOUT ANY WARRANTY; without even the implied
- * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
- * You should have received a copy of the GNU General Public License  along with this program.
- * If not, see <http://www.gnu.org/licenses/>
- *
- ******************************************************************************/
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
 
-package io.github.dsheirer.module.decode.p25.audio;
+package io.github.dsheirer.audio.codec.mbe;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonInclude;
@@ -27,7 +30,7 @@ import com.fasterxml.jackson.annotation.JsonRootName;
  */
 @JsonRootName(value = "frame")
 @JsonInclude(JsonInclude.Include.NON_NULL)
-@JsonPropertyOrder({"encryption_algorithm", "encryption_key_id", "encryption_mi", "time", "hex"})
+@JsonPropertyOrder({"tag", "encryption_algorithm", "encryption_key_id", "encryption_mi", "time", "hex"})
 public class VoiceFrame
 {
     private long mTimestamp;
@@ -35,6 +38,7 @@ public class VoiceFrame
     private Integer mAlgorithm;
     private Integer mKeyId;
     private String mMessageIndicator;
+    private String mTag;
 
     public VoiceFrame()
     {
@@ -70,6 +74,24 @@ public class VoiceFrame
         mMessageIndicator = messageIndicator;
     }
 
+    /**
+     * Tag value for the voice frame
+     */
+    @JsonProperty("tag")
+    public String getTag()
+    {
+        return mTag;
+    }
+
+    /**
+     * Sets the optional tag value for the frame
+     * @param tag to set
+     */
+    public void setTag(String tag)
+    {
+        mTag = tag;
+    }
+
     /**
      * Timestamp the frame was transmitted
      *

src/main/java/io/github/dsheirer/audio/playback/AudioChannel.java

@@ -0,0 +1,638 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.audio.playback;
+
+import com.google.common.eventbus.Subscribe;
+import io.github.dsheirer.audio.AudioEvent;
+import io.github.dsheirer.audio.AudioSegment;
+import io.github.dsheirer.eventbus.MyEventBus;
+import io.github.dsheirer.identifier.IdentifierCollection;
+import io.github.dsheirer.identifier.IdentifierUpdateNotification;
+import io.github.dsheirer.preference.PreferenceType;
+import io.github.dsheirer.preference.UserPreferences;
+import io.github.dsheirer.sample.Broadcaster;
+import io.github.dsheirer.sample.Listener;
+import java.util.Arrays;
+import java.util.concurrent.LinkedTransferQueue;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Manages the incoming audio segments and provides access to audio buffers from those segments.
+ */
+public class AudioChannel implements Listener<IdentifierUpdateNotification>
+{
+    /**
+     * Quantity of audio samples to deliver per getAudio() method invocation, equivalent to 20 milliseconds at an 8 kHz
+     * sample rate.
+     */
+    public static final int SAMPLES_PER_INTERVAL = 160;
+    private static final Logger LOGGER = LoggerFactory.getLogger(AudioChannel.class);
+    private final AudioBuffer mAudioBuffer = new AudioBuffer();
+    private final Broadcaster<AudioEvent> mAudioEventBroadcaster = new Broadcaster<>();
+    private final LinkedTransferQueue<AudioSegment> mAudioSegmentQueue = new LinkedTransferQueue<>();
+    private final UserPreferences mUserPreferences;
+    private final String mChannelName;
+
+    private AudioSegment mCurrentAudioSegment;
+    private Listener<IdentifierCollection> mIdentifierCollectionListener;
+    private boolean mDropDuplicates;
+    private boolean mMetadataSent = false;
+    private boolean mMuted;
+    private boolean mDisabled;
+    private float[] mAudioSegmentStartTone;
+    private float[] mAudioSegmentDropTone;
+    private int mCurrentBufferIndex = -1;
+    private int mNoAudioFromSegmentIntervalCount = 0;
+
+    /**
+     * Constructs an instance
+     */
+    public AudioChannel(UserPreferences userPreferences, String channelName)
+    {
+        mUserPreferences = userPreferences;
+        mChannelName = channelName;
+
+        mDropDuplicates = mUserPreferences.getCallManagementPreference().isDuplicatePlaybackSuppressionEnabled();
+        updateToneInsertionAudioClips();
+
+        //Register to receive preference update notifications so we can update the preference items
+        MyEventBus.getGlobalEventBus().register(this);
+    }
+
+    /**
+     * Enables or disables this audio channel.
+     * @param disabled state
+     */
+    public void setDisabled(boolean disabled)
+    {
+        mDisabled = disabled;
+
+        if(disabled)
+        {
+            AudioSegment segment = mAudioSegmentQueue.poll();
+
+            while(segment != null)
+            {
+                segment.decrementConsumerCount();
+                segment = mAudioSegmentQueue.poll();
+            }
+        }
+    }
+
+    /**
+     * Indicates if this audio channel is enabled.
+     */
+    public boolean isDisabled()
+    {
+        return mDisabled;
+    }
+
+    /**
+     * Switches this channel's muted state
+     * @param muted true to mute and false to unmute
+     */
+    public void setMuted(boolean muted)
+    {
+        mMuted = muted;
+        notify(muted ? AudioEvent.Type.AUDIO_MUTED : AudioEvent.Type.AUDIO_UNMUTED);
+    }
+
+    /**
+     * Indicates if this channel is muted
+     * @return muted state
+     */
+    public boolean isMuted()
+    {
+        return mMuted;
+    }
+
+    /**
+     * Plays the test audio sample data at higher priority that current audio queue.
+     * @param samples of test audio to play.
+     */
+    public void playTest(float[] samples)
+    {
+        if(isDisabled())
+        {
+            return;
+        }
+
+        mAudioBuffer.insert(samples);
+    }
+
+    /**
+     * Indicates if this channel has an audio segment, indicating that it is right in the middle of playback and
+     * the audio output should temporarily pause until more audio is available from the segment.
+     * @return true if this channel is processing a non-complete audio segment.
+     */
+    public boolean hasAudioSegment()
+    {
+        return mCurrentAudioSegment != null;
+    }
+
+    /**
+     * Broadcasts a null identifier collection to the UI to clear any displayed metadata (TO/FROM) identifiers
+     */
+    public void clearMetadata()
+    {
+        if(mMetadataSent)
+        {
+            broadcast(null);
+            mMetadataSent = false;
+        }
+    }
+
+    /**
+     * Provides audio for this channel from the audio segment queue.
+     * @return audio or null if there are no audio segments or test audio to play.
+     */
+    public float[] getAudio()
+    {
+        if(mAudioBuffer.isFull())
+        {
+            float[] audio = mAudioBuffer.get();
+
+            if(isMuted())
+            {
+                return new float[SAMPLES_PER_INTERVAL];
+            }
+            else
+            {
+                return audio;
+            }
+        }
+
+        if(mCurrentAudioSegment == null)
+        {
+            loadNextAudioSegment();
+        }
+
+        //Evaluate current audio segment to see if the status has changed for duplicate or do-not-monitor.
+        while(isThrowaway(mCurrentAudioSegment))
+        {
+            if(mCurrentBufferIndex > 0)
+            {
+                //Flush the buffer and insert the drop tone
+                mAudioBuffer.replace(mAudioSegmentDropTone);
+            }
+
+            disposeCurrentAudioSegment();
+            loadNextAudioSegment();
+        }
+
+        if(mCurrentAudioSegment != null)
+        {
+            mNoAudioFromSegmentIntervalCount++;
+        }
+
+        while(!mAudioBuffer.isFull() && mCurrentAudioSegment != null &&
+                mCurrentBufferIndex < mCurrentAudioSegment.getAudioBufferCount())
+        {
+            if(mCurrentBufferIndex < 0)
+            {
+                mAudioBuffer.add(mAudioSegmentStartTone);
+                mAudioBuffer.add(mCurrentAudioSegment.getAudioBuffer(0));
+                mCurrentBufferIndex = 1;
+                broadcast(mCurrentAudioSegment.getIdentifierCollection());
+                mMetadataSent = true;
+            }
+            else
+            {
+                mAudioBuffer.add(mCurrentAudioSegment.getAudioBuffer(mCurrentBufferIndex++));
+            }
+
+            mNoAudioFromSegmentIntervalCount = 0;
+        }
+
+        //Dispose completed/fully-played audio segments and segments that have stalled/failed to progress
+        if(mCurrentAudioSegment != null && ((mNoAudioFromSegmentIntervalCount >= 6) ||
+          (mCurrentAudioSegment.isComplete() && (mCurrentBufferIndex >= mCurrentAudioSegment.getAudioBufferCount()))))
+        {
+            disposeCurrentAudioSegment();
+            mNoAudioFromSegmentIntervalCount = 0;
+        }
+
+        float[] audio = null;
+
+        if(mAudioBuffer.isFull())
+        {
+            audio = mAudioBuffer.get();
+        }
+        else if(mCurrentAudioSegment == null && !mAudioBuffer.isEmpty())
+        {
+            audio = mAudioBuffer.flush();
+        }
+
+        //Finally, if we have buffer audio and we're muted, return silence
+        if(isMuted() && audio != null)
+        {
+            audio = new float[SAMPLES_PER_INTERVAL];
+        }
+
+        return audio;
+    }
+
+    /**
+     * Notifies listener(s) of the audio event.
+     * @param eventType to notify for this channel
+     */
+    public void notify(AudioEvent.Type eventType)
+    {
+        broadcastAudioEvent(new AudioEvent(eventType, getChannelName()));
+    }
+    /**
+     * Registers a single listener to receive audio start and audio stop events
+     */
+    public void addAudioEventListener(Listener<AudioEvent> listener)
+    {
+        mAudioEventBroadcaster.addListener(listener);
+    }
+
+    /**
+     * Removes the audio event listener
+     * @param listener to remove
+     */
+    public void removeAudioEventListener(Listener<AudioEvent> listener)
+    {
+        mAudioEventBroadcaster.removeListener(listener);
+    }
+
+    /**
+     * Broadcasts an audio event to the registered listener
+     */
+    private void broadcastAudioEvent(AudioEvent audioEvent)
+    {
+        mAudioEventBroadcaster.broadcast(audioEvent);
+    }
+
+    /**
+     * Indicates if the audio segment should be thrown away because it is marked as duplicate or do-not-monitor.
+     * @param audioSegment to evaluate
+     * @return true if the audio should be thrown away.
+     */
+    private boolean isThrowaway(AudioSegment audioSegment)
+    {
+        return audioSegment != null && (audioSegment.isDoNotMonitor() || mDropDuplicates && (audioSegment.isDuplicate()));
+    }
+
+    /**
+     * Channel name
+     */
+    public String getChannelName()
+    {
+        return mChannelName;
+    }
+
+    /**
+     * Broadcasts audio identifier collection metadata to the registered listener
+     */
+    private void broadcast(IdentifierCollection identifierCollection)
+    {
+        if(mIdentifierCollectionListener != null)
+        {
+            mIdentifierCollectionListener.receive(identifierCollection);
+        }
+    }
+
+    /**
+     * Registers a single listener to receive the audio metadata from each
+     * audio packet
+     */
+    public void setIdentifierCollectionListener(Listener<IdentifierCollection> listener)
+    {
+        mIdentifierCollectionListener = listener;
+    }
+
+    /**
+     * Unregisters the current audio metadata listener
+     */
+    public void removeAudioMetadataListener()
+    {
+        mIdentifierCollectionListener = null;
+    }
+
+    /**
+     * Prepares this audio output for disposal.
+     */
+    public void dispose()
+    {
+
+        MyEventBus.getGlobalEventBus().unregister(this);
+        disposeCurrentAudioSegment();
+        mAudioEventBroadcaster.clear();
+        mIdentifierCollectionListener = null;
+    }
+
+    /**
+     * Guava event bus notifications that the preferences have been updated, so that we can update audio segment tones.
+     */
+    @Subscribe
+    public void preferenceUpdated(PreferenceType preferenceType)
+    {
+        if(preferenceType == PreferenceType.PLAYBACK)
+        {
+            updateToneInsertionAudioClips();
+        }
+        else if(preferenceType == PreferenceType.DUPLICATE_CALL_DETECTION)
+        {
+            mDropDuplicates = mUserPreferences.getCallManagementPreference().isDuplicatePlaybackSuppressionEnabled();
+        }
+    }
+
+    /**
+     * Indicates if the audio segment is linked to the current playback audio segment
+     */
+    public boolean isLinkedTo(AudioSegment audioSegment)
+    {
+        return audioSegment.isLinked() && audioSegment.isLinkedTo(mCurrentAudioSegment);
+    }
+
+    /**
+     * Receive and process audio identifier update notifications.
+     */
+    public void receive(IdentifierUpdateNotification identifierUpdateNotification)
+    {
+        if(mCurrentAudioSegment != null)
+        {
+            IdentifierCollection identifierCollection = mCurrentAudioSegment.getIdentifierCollection();
+
+            if(identifierCollection != null)
+            {
+                broadcast(identifierCollection);
+            }
+        }
+    }
+
+    /**
+     * Updates audio segment start, drop and preempt tone insertion clips
+     */
+    private void updateToneInsertionAudioClips()
+    {
+        mAudioSegmentStartTone = mUserPreferences.getPlaybackPreference().getStartTone();
+        mAudioSegmentDropTone = mUserPreferences.getPlaybackPreference().getDropTone();;
+    }
+
+    /**
+     * Indicates if this audio output doesn't currently have any audio segments queued for playback.
+     * @return true if empty
+     */
+    public boolean isEmpty()
+    {
+        return mAudioSegmentQueue.isEmpty();
+    }
+
+    /**
+     * Schedules the audio segment for playback.  The audio segment user count should already be incremented by the
+     * calling entity.
+     *
+     * @param audioSegment to schedule for playback.
+     */
+    public void play(AudioSegment audioSegment)
+    {
+        if(audioSegment != null)
+        {
+            //Audio segment user count has already been incremented by the external caller.
+            if(isDisabled())
+            {
+                audioSegment.decrementConsumerCount();
+            }
+            else
+            {
+                mAudioSegmentQueue.add(audioSegment);
+            }
+        }
+    }
+
+    /**
+     * Dispose of the currently assigned audio segment.
+     */
+    private void disposeCurrentAudioSegment()
+    {
+        if(mCurrentAudioSegment != null)
+        {
+            mCurrentAudioSegment.decrementConsumerCount();
+            mCurrentAudioSegment.removeIdentifierUpdateNotificationListener(this);
+            mCurrentAudioSegment = null;
+        }
+    }
+
+    /**
+     * Loads the next audio segment from the queue.
+     */
+    private void loadNextAudioSegment()
+    {
+        AudioSegment audioSegment = mAudioSegmentQueue.poll();
+
+        boolean verificationInProgress = (audioSegment != null);
+
+        while(verificationInProgress)
+        {
+            if(audioSegment != null)
+            {
+                //Throw away the audio segment if it has been flagged as do not monitor or is duplicate
+                if(isThrowaway(audioSegment))
+                {
+                    audioSegment.decrementConsumerCount();
+                    audioSegment = mAudioSegmentQueue.poll();
+                }
+                else
+                {
+                    verificationInProgress = false;
+                }
+            }
+            else
+            {
+                verificationInProgress = false;
+            }
+        }
+
+        mCurrentAudioSegment = audioSegment;
+
+        if(audioSegment != null)
+        {
+            mCurrentAudioSegment.addIdentifierUpdateNotificationListener(this);
+            broadcast(mCurrentAudioSegment.getIdentifierCollection());
+        }
+
+        mCurrentBufferIndex = -1;
+    }
+
+    /**
+     * Manages a stream of float PCM audio samples.  Employs thread locking of the audio buffer to support both the
+     * audio processor thread and user initiated test audio replay.
+     */
+    static class AudioBuffer
+    {
+        private final Lock mLock = new ReentrantLock();
+        private float[] mBuffer = new float[0];
+
+        /**
+         * Indicates if the buffer has at least one interval of samples available
+         */
+        public boolean isFull()
+        {
+            return mBuffer.length >= SAMPLES_PER_INTERVAL;
+        }
+
+        /**
+         * Indicates if the buffer is empty
+         */
+        public boolean isEmpty()
+        {
+            return mBuffer.length == 0;
+        }
+
+        /**
+         * Appends the audio to the buffer
+         * @param audio to add
+         */
+        public void add(float[] audio)
+        {
+            if(audio != null)
+            {
+                mLock.lock();
+
+                try
+                {
+                    mBuffer = concatenate(mBuffer, audio);
+                }
+                finally
+                {
+                    mLock.unlock();
+                }
+            }
+        }
+
+        /**
+         * Inserts the audio to the front of the buffer.  This can be used to insert test audio ahead of any queued audio.
+         * @param audio to insert
+         */
+        public void insert(float[] audio)
+        {
+            if(audio != null)
+            {
+                mLock.lock();
+                try
+                {
+                    mBuffer = concatenate(audio, mBuffer);
+                }
+                finally
+                {
+                    mLock.unlock();
+                }
+            }
+        }
+
+        /**
+         * Replaces the content in the buffer with the audio argument
+         * @param audio to replace into the buffer
+         */
+        public void replace(float[] audio)
+        {
+            if(audio != null)
+            {
+                mLock.lock();
+
+                try
+                {
+                    mBuffer = audio;
+                }
+                finally
+                {
+                    mLock.unlock();
+                }
+            }
+        }
+
+        /**
+         * Concatenate two arrays.  Note: this does not null check either array.
+         * @param a first array
+         * @param b second array
+         * @return concatenated array
+         */
+        private static float[] concatenate(float[] a, float[] b)
+        {
+            a = Arrays.copyOf(a, a.length + b.length);
+            System.arraycopy(b, 0, a, a.length - b.length, b.length);
+            return a;
+        }
+
+        /**
+         * Retrieves an array of 160 samples if available, otherwise returns null.
+         * @return 160 samples or null.
+         */
+        public float[] get()
+        {
+            if(mBuffer.length >= SAMPLES_PER_INTERVAL)
+            {
+                mLock.lock();
+                try
+                {
+                    float[] fragment = Arrays.copyOf(mBuffer, SAMPLES_PER_INTERVAL);
+                    mBuffer = Arrays.copyOfRange(mBuffer, SAMPLES_PER_INTERVAL, mBuffer.length);
+                    return fragment;
+                }
+                finally
+                {
+                    mLock.unlock();
+                }
+            }
+
+            return null;
+        }
+
+        /**
+         * Flushes remaining samples from the buffer when the quantity is less than a full sample set.
+         * @return remaining samples or null.
+         */
+        public float[] flush()
+        {
+            mLock.lock();
+
+            try
+            {
+                if(mBuffer.length > 0)
+                {
+                    float[] fragment = Arrays.copyOf(mBuffer, SAMPLES_PER_INTERVAL);
+
+                    if(mBuffer.length > SAMPLES_PER_INTERVAL)
+                    {
+                        mBuffer = Arrays.copyOfRange(mBuffer, SAMPLES_PER_INTERVAL, mBuffer.length);
+                    }
+                    else
+                    {
+                        mBuffer = new float[0];
+                    }
+
+                    return fragment;
+                }
+
+                return null;
+            }
+            finally
+            {
+                mLock.unlock();
+            }
+        }
+    }
+}

src/main/java/io/github/dsheirer/audio/playback/AudioChannelPanel.java

@@ -1,7 +1,6 @@
 /*
- * ******************************************************************************
- * sdrtrunk
- * Copyright (C) 2014-2019 Dennis Sheirer
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -15,7 +14,7 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>
- * *****************************************************************************
+ * ****************************************************************************
  */
 package io.github.dsheirer.audio.playback;
 
@@ -40,13 +39,6 @@ import io.github.dsheirer.settings.ColorSetting;
 import io.github.dsheirer.settings.Setting;
 import io.github.dsheirer.settings.SettingChangeListener;
 import io.github.dsheirer.settings.SettingsManager;
-import net.miginfocom.swing.MigLayout;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import javax.swing.ImageIcon;
-import javax.swing.JLabel;
-import javax.swing.JPanel;
 import java.awt.Color;
 import java.awt.EventQueue;
 import java.awt.Font;
@@ -54,7 +46,17 @@ import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
+import net.miginfocom.swing.MigLayout;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
+import javax.swing.ImageIcon;
+import javax.swing.JLabel;
+import javax.swing.JPanel;
+
+/**
+ * UI to wrap an audio channel and provide display of metadata and playback state information.
+ */
 public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, SettingChangeListener
 {
     private static final long serialVersionUID = 1L;
@@ -66,30 +68,36 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
     public static final String PROPERTY_COLOR_MUTED = PROPERTY_PREFIX + "muted";
     public static final String PROPERTY_COLOR_VALUE = PROPERTY_PREFIX + "value";
 
-    private Font mFont = new Font(Font.MONOSPACED, Font.PLAIN, 16);
-
-    private Color mBackgroundColor;
-    private Color mLabelColor;
-    private Color mMutedColor;
-    private Color mValueColor;
-
-    private IconModel mIconModel;
-    private SettingsManager mSettingsManager;
-    private UserPreferences mUserPreferences;
-    private TalkgroupFormatPreference mTalkgroupFormatPreference;
-    private AudioOutput mAudioOutput;
-
-    private JLabel mMutedLabel = new JLabel("M");
-    private JLabel mChannelName = new JLabel(" ");
-    private JLabel mIconLabel = new JLabel(" ");
-    private JLabel mIdentifierLabel = new JLabel("-----");
+    private final AudioChannel mAudioChannel;
+    private final AliasModel mAliasModel;
+    private final IconModel mIconModel;
+    private final SettingsManager mSettingsManager;
+    private final UserPreferences mUserPreferences;
+    private final TalkgroupFormatPreference mTalkgroupFormatPreference;
     private Identifier mIdentifier;
     private List<Alias> mAliases = Collections.EMPTY_LIST;
-    private AliasModel mAliasModel;
-    private Lock mLock = new ReentrantLock();
+    private final Lock mLock = new ReentrantLock();
 
-    public AudioChannelPanel(IconModel iconModel, UserPreferences userPreferences, SettingsManager settingsManager,
-                             AudioOutput audioOutput, AliasModel aliasModel)
+    private final Font mFont = new Font(Font.MONOSPACED, Font.PLAIN, 16);
+    private final Color mBackgroundColor;
+    private final Color mLabelColor;
+    private final Color mMutedColor;
+    private final Color mValueColor;
+    private final JLabel mMutedLabel = new JLabel("M");
+    private JLabel mChannelName = new JLabel(" ");
+    private final JLabel mIconLabel = new JLabel(" ");
+    private final JLabel mIdentifierLabel = new JLabel("-----");
+
+    /**
+     * Constructs an instance
+     * @param audioChannel to wrap by this panel
+     * @param aliasModel for alias lookup
+     * @param iconModel for icon lookup
+     * @param settingsManager for monitoring changes to tone insertion
+     * @param userPreferences for lookup of tone and other preferences
+     */
+    public AudioChannelPanel(AudioChannel audioChannel, AliasModel aliasModel, IconModel iconModel,
+                             SettingsManager settingsManager, UserPreferences userPreferences)
     {
         mIconModel = iconModel;
         mSettingsManager = settingsManager;
@@ -97,12 +105,12 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
         mAliasModel = aliasModel;
         mUserPreferences = userPreferences;
         mTalkgroupFormatPreference = mUserPreferences.getTalkgroupFormatPreference();
-        mAudioOutput = audioOutput;
+        mAudioChannel = audioChannel;
 
-        if(mAudioOutput != null)
+        if(mAudioChannel != null)
         {
-            mAudioOutput.addAudioEventListener(this);
-            mAudioOutput.setIdentifierCollectionListener(new AudioMetadataProcessor());
+            mAudioChannel.addAudioEventListener(this);
+            mAudioChannel.setIdentifierCollectionListener(new AudioMetadataProcessor());
         }
 
         mBackgroundColor = SystemProperties.getInstance().get(PROPERTY_COLOR_BACKGROUND, Color.BLACK);
@@ -131,10 +139,10 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
         //Deregister from receiving preference update notifications
         MyEventBus.getGlobalEventBus().unregister(this);
 
-        if(mAudioOutput != null)
+        if(mAudioChannel != null)
         {
-            mAudioOutput.removeAudioEventListener(this);
-            mAudioOutput.removeAudioMetadataListener();
+            mAudioChannel.removeAudioEventListener(this);
+            mAudioChannel.removeAudioMetadataListener();
         }
     }
 
@@ -152,7 +160,7 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
         mMutedLabel.setVisible(false);
         add(mMutedLabel);
 
-        mChannelName = new JLabel(mAudioOutput != null ? mAudioOutput.getChannelName() : " ");
+        mChannelName = new JLabel(mAudioChannel != null ? mAudioChannel.getChannelName() : " ");
         mChannelName.setFont(mFont);
         mChannelName.setForeground(mLabelColor);
         add(mChannelName);
@@ -172,25 +180,11 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
         switch(audioEvent.getType())
         {
             case AUDIO_STOPPED:
-                EventQueue.invokeLater(new Runnable()
-                {
-                    @Override
-                    public void run()
-                    {
-                        resetLabels();
-                    }
-                });
+                EventQueue.invokeLater(this::resetLabels);
                 break;
             case AUDIO_MUTED:
             case AUDIO_UNMUTED:
-                EventQueue.invokeLater(new Runnable()
-                {
-                    @Override
-                    public void run()
-                    {
-                        mMutedLabel.setVisible(mAudioOutput.isMuted());
-                    }
-                });
+                EventQueue.invokeLater(() -> mMutedLabel.setVisible(mAudioChannel.isMuted()));
                 break;
             default:
                 break;

src/main/java/io/github/dsheirer/audio/playback/AudioChannelsPanel.java

@@ -1,7 +1,6 @@
 /*
- * ******************************************************************************
- * sdrtrunk
- * Copyright (C) 2014-2019 Dennis Sheirer
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -15,7 +14,7 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>
- * *****************************************************************************
+ * ****************************************************************************
  */
 package io.github.dsheirer.audio.playback;
 
@@ -24,18 +23,26 @@ import io.github.dsheirer.audio.IAudioController;
 import io.github.dsheirer.icon.IconModel;
 import io.github.dsheirer.preference.UserPreferences;
 import io.github.dsheirer.settings.SettingsManager;
+import java.awt.Color;
+import java.awt.Component;
 import net.miginfocom.swing.MigLayout;
 
 import javax.swing.JPanel;
 import javax.swing.JSeparator;
-import java.awt.Color;
-import java.awt.Component;
-import java.util.List;
 
+/**
+ * Displays one or more audio channel panels.
+ */
 public class AudioChannelsPanel extends JPanel
 {
-    private static final long serialVersionUID = 1L;
-
+    /**
+     * Constructs an instance
+     * @param iconModel for icon access
+     * @param userPreferences to monitor for audio playback changes
+     * @param settingsManager for tone insertion settings
+     * @param controller for the audio channels
+     * @param aliasModel for accessing aliases
+     */
     public AudioChannelsPanel(IconModel iconModel, UserPreferences userPreferences, SettingsManager settingsManager,
                               IAudioController controller, AliasModel aliasModel)
     {
@@ -44,15 +51,13 @@ public class AudioChannelsPanel extends JPanel
 
         setBackground(Color.BLACK);
 
-        List<AudioOutput> outputs = controller.getAudioOutputs();
-
         addSeparator();
 
-        for(int x = 0; x < outputs.size(); x++)
+        for(int x = 0; x < controller.getAudioChannels().size(); x++)
         {
-            add(new AudioChannelPanel(iconModel, userPreferences, settingsManager, outputs.get(x), aliasModel));
+            add(new AudioChannelPanel(controller.getAudioChannels().get(x), aliasModel, iconModel, settingsManager, userPreferences));
 
-            if(x < outputs.size() - 1)
+            if(x < controller.getAudioChannels().size() - 1)
             {
                 addSeparator();
             }
@@ -60,10 +65,10 @@ public class AudioChannelsPanel extends JPanel
 
 		/* Add an empty channel panel so that the panel is sized appropriately
          * for either a single channel or two channels */
-        if(outputs.size() == 1)
+        if(controller.getAudioChannels().size() == 1)
         {
             addSeparator();
-            add(new AudioChannelPanel(iconModel, userPreferences, settingsManager, null, aliasModel), "growx");
+            add(new AudioChannelPanel(null, aliasModel, iconModel, settingsManager, userPreferences), "growx");
         }
     }
 
@@ -81,6 +86,9 @@ public class AudioChannelsPanel extends JPanel
         }
     }
 
+    /**
+     * Adds a separator to this panel.
+     */
     private void addSeparator()
     {
         JSeparator separator = new JSeparator(JSeparator.VERTICAL);

src/main/java/io/github/dsheirer/audio/playback/AudioOutput.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2025 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -18,22 +18,14 @@
  */
 package io.github.dsheirer.audio.playback;
 
-import com.google.common.eventbus.Subscribe;
 import io.github.dsheirer.audio.AudioEvent;
-import io.github.dsheirer.audio.AudioSegment;
 import io.github.dsheirer.controller.NamingThreadFactory;
-import io.github.dsheirer.eventbus.MyEventBus;
-import io.github.dsheirer.identifier.IdentifierCollection;
-import io.github.dsheirer.identifier.IdentifierUpdateNotification;
 import io.github.dsheirer.log.LoggingSuppressor;
-import io.github.dsheirer.preference.PreferenceType;
-import io.github.dsheirer.preference.UserPreferences;
-import io.github.dsheirer.sample.Broadcaster;
-import io.github.dsheirer.sample.Listener;
-import io.github.dsheirer.source.mixer.MixerChannel;
+import io.github.dsheirer.preference.playback.PlayTestAudioRequest;
 import java.nio.ByteBuffer;
+import java.util.Arrays;
+import java.util.List;
 import java.util.concurrent.Executors;
-import java.util.concurrent.LinkedTransferQueue;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.TimeUnit;
@@ -41,11 +33,10 @@ import java.util.concurrent.atomic.AtomicBoolean;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.sound.sampled.AudioFormat;
-import javax.sound.sampled.BooleanControl;
+import javax.sound.sampled.AudioSystem;
 import javax.sound.sampled.Control;
+import javax.sound.sampled.DataLine;
 import javax.sound.sampled.FloatControl;
-import javax.sound.sampled.Line;
 import javax.sound.sampled.LineEvent;
 import javax.sound.sampled.LineListener;
 import javax.sound.sampled.LineUnavailableException;
@@ -56,418 +47,214 @@ import javax.sound.sampled.SourceDataLine;
  * Audio output/playback channel for a single audio mixer channel.  Providers support for playback of audio segments
  * and broadcasts audio segment metadata to registered listeners (ie gui components).
  */
-public abstract class AudioOutput implements LineListener, Listener<IdentifierUpdateNotification>
+public class AudioOutput implements LineListener
 {
-    private final static Logger mLog = LoggerFactory.getLogger(AudioOutput.class);
+    private static final Logger mLog = LoggerFactory.getLogger(AudioOutput.class);
     private static final LoggingSuppressor LOGGING_SUPPRESSOR = new LoggingSuppressor(mLog);
-    private int mBufferStartThreshold;
-    private int mBufferStopThreshold;
-    private Listener<IdentifierCollection> mIdentifierCollectionListener;
-    private Broadcaster<AudioEvent> mAudioEventBroadcaster = new Broadcaster<>();
-    private SourceDataLine mOutput;
-    private Mixer mMixer;
-    private MixerChannel mMixerChannel;
+    private static final int BUFFER_SIZE_SAMPLES = 1000; //At 8 kHz audio
+    private final AudioPlaybackDeviceDescriptor mAudioPlaybackDeviceDescriptor;
+    private final AudioProvider mAudioProvider;
     private FloatControl mGainControl;
-    private BooleanControl mMuteControl;
-    private AudioEvent mAudioStartEvent;
-    private AudioEvent mAudioStopEvent;
-    private boolean mCanProcessAudio = false;
-    private LinkedTransferQueue<AudioSegment> mAudioSegmentQueue = new LinkedTransferQueue<>();
-    private AudioSegment mCurrentAudioSegment;
-    private int mCurrentBufferIndex = 0;
-    private UserPreferences mUserPreferences;
-    private ByteBuffer mAudioSegmentStartTone;
-    private ByteBuffer mAudioSegmentDropTone;
-    private boolean mRunning = false;
     private ScheduledExecutorService mScheduledExecutorService;
     private ScheduledFuture<?> mProcessorFuture;
-    private boolean mDropDuplicates;
-    private long mOutputLastTimestamp = 0;
-    private static final long STALE_PLAYBACK_THRESHOLD_MS = 500;
-    private AudioFormat mAudioFormat;
-    private Line.Info mLineInfo;
-    private int mRequestedBufferSize;
+    private SourceDataLine mSourceDataLine;
+    private boolean mCanProcessAudio = false;
+    private boolean mRunning = false;
+
 
     /**
-     * Single audio channel playback with automatic starting and stopping of the
-     * underlying sourcedataline specified by the mixer and mixer channel
-     * arguments.
+     * Audio output for the selected audio playback device and provider.  Opens a SourceDataLine from the miser for the
+     * audio format specified in the descriptor.  Employs a single threaded executor to process audio 10x a second and
+     * manages the start/stop control for the dataline based on audio availability.
      *
-     * Maintains an internal non-blocking audio packet queue and processes this
-     * queue 25 times a second (every 40 ms).
-     *
-     * @param mixer to obtain source data line
-     * @param mixerChannel either mono or left/right stereo
-     * @param audioFormat to use during playback
-     * @param lineInfo to use when obtaining the source data line
-     * @param requestedBufferSize of approximately 1 second of audio
+     * @param descriptor for the mixer and audio format
+     * @param audioProvider for access to audio from audio segments
      */
-    public AudioOutput(Mixer mixer, MixerChannel mixerChannel, AudioFormat audioFormat, Line.Info lineInfo,
-                       int requestedBufferSize, UserPreferences userPreferences)
+    public AudioOutput(AudioPlaybackDeviceDescriptor descriptor, AudioProvider audioProvider)
     {
-        mMixer = mixer;
-        mMixerChannel = mixerChannel;
-        mScheduledExecutorService = Executors.newSingleThreadScheduledExecutor(new NamingThreadFactory(
-                "sdrtrunk audio output " + mixerChannel.name()));
-        mUserPreferences = userPreferences;
-        mDropDuplicates = mUserPreferences.getCallManagementPreference().isDuplicatePlaybackSuppressionEnabled();
-        mAudioFormat = audioFormat;
-        mLineInfo = lineInfo;
-        mRequestedBufferSize = requestedBufferSize;
+        mAudioProvider = audioProvider;
+        Mixer mixer = AudioSystem.getMixer(descriptor.getMixerInfo());
 
-        try
+        if(mixer == null)
         {
-            mOutput = (SourceDataLine) mMixer.getLine(mLineInfo);
+            List<AudioPlaybackDeviceDescriptor> descriptors = AudioPlaybackDeviceManager.getAudioPlaybackDevices();
 
-            if(mOutput != null)
+            int selected = 0;
+
+            while((mixer == null) && (selected < descriptors.size()))
             {
-                mOutput.open(audioFormat, requestedBufferSize);
+                descriptor = descriptors.get(selected++);
+                mixer = AudioSystem.getMixer(descriptor.getMixerInfo());
+            }
+        }
 
-                //Start threshold: buffer is full with 10% or less of capacity remaining
-                mBufferStartThreshold = (int) (mOutput.getBufferSize() * 0.10);
+        mAudioPlaybackDeviceDescriptor = descriptor;
 
-                //Stop threshold: buffer is empty with 90% or more capacity available
-                mBufferStopThreshold = (int) (mOutput.getBufferSize() * 0.90);
+        if(mixer != null)
+        {
+            try
+            {
+                mSourceDataLine = (SourceDataLine) mixer.getLine(new DataLine.Info(SourceDataLine.class,
+                        descriptor.getAudioFormat()));
 
-                mOutput.addLineListener(this);
-
-                if(mOutput != null)
+                if(mSourceDataLine != null)
                 {
+                    mSourceDataLine.addLineListener(this);
                     try
                     {
-                        Control gain = mOutput.getControl(FloatControl.Type.MASTER_GAIN);
+                        Control gain = mSourceDataLine.getControl(FloatControl.Type.MASTER_GAIN);
                         mGainControl = (FloatControl) gain;
                     }
                     catch(IllegalArgumentException iae)
                     {
                         LOGGING_SUPPRESSOR.error("no gain control", 2, "Couldn't obtain " +
-                            "MASTER GAIN control for stereo line [" + mixer.getMixerInfo().getName() + " | " +
-                                getChannelName() + "]");
+                                "MASTER GAIN control for stereo line [" + mixer.getMixerInfo().getName() + "]");
                     }
 
-                    try
-                    {
-                        Control mute = mOutput.getControl(BooleanControl.Type.MUTE);
-                        mMuteControl = (BooleanControl) mute;
-                    }
-                    catch(IllegalArgumentException iae)
-                    {
-                        LOGGING_SUPPRESSOR.error("no mute control", 2, "Couldn't obtain " +
-                            "MUTE control for stereo line [" + mixer.getMixerInfo().getName() + " | " +
-                            getChannelName() + "]");
-                    }
-
-					//Run the queue processor task every 100 milliseconds or 10 times a second
-                    mProcessorFuture = mScheduledExecutorService.scheduleAtFixedRate(new AudioSegmentProcessor(),
-                        0, 100, TimeUnit.MILLISECONDS);
+                    mCanProcessAudio = true;
                 }
+            }
+            catch(LineUnavailableException e)
+            {
+                mLog.error("Couldn't open source data line for mixer: " + descriptor.getMixerInfo().getName(), e);
+            }
 
-                mAudioStartEvent = new AudioEvent(AudioEvent.Type.AUDIO_STARTED, getChannelName());
-                mAudioStopEvent = new AudioEvent(AudioEvent.Type.AUDIO_STOPPED, getChannelName());
-                mCanProcessAudio = true;
+            if(mCanProcessAudio)
+            {
+                openSourceDataLine();
+
+                //The audio provider gives us audio 160 samples per interval representing 20 milliseconds of audio.
+                // Run the scheduled executor at just slightly faster than that time, recognizing that it will
+                // block against the mixer source data line until it can write all 160 samples.
+                mScheduledExecutorService = Executors.newSingleThreadScheduledExecutor(new NamingThreadFactory(
+                        "sdrtrunk audio output " + descriptor.getMixerInfo().getName()));
+                mProcessorFuture = mScheduledExecutorService.scheduleAtFixedRate(new AudioProcessor(),
+                        0, 19, TimeUnit.MILLISECONDS);
+            }
+            else
+            {
+                //Disable each of the audio channels so they don't queue audio segments.
+                for(AudioChannel audioChannel: mAudioProvider.getAudioChannels())
+                {
+                    audioChannel.setDisabled(true);
+                }
+            }
+        }
+    }
+
+    /**
+     * Opens and starts the source data line.
+     */
+    private void openSourceDataLine()
+    {
+        try
+        {
+            if(mSourceDataLine != null && !mSourceDataLine.isOpen())
+            {
+                int bufferSize = BUFFER_SIZE_SAMPLES * 2 * mAudioPlaybackDeviceDescriptor.getAudioFormat().getChannels();
+                mSourceDataLine.open(mAudioProvider.getAudioFormat(), bufferSize);
+                bufferSize = mSourceDataLine.getBufferSize();
+                //Fill the line with silence so we can start it
+                mSourceDataLine.write(new byte[bufferSize], 0, bufferSize);
+                mSourceDataLine.start();
+
+                for(AudioChannel audioChannel: mAudioProvider.getAudioChannels())
+                {
+                    audioChannel.setDisabled(false);
+                }
             }
         }
         catch(LineUnavailableException e)
         {
-            mLog.error("Couldn't obtain audio source data line for audio output - mixer [" +
-                mMixer.getMixerInfo().getName() + "]");
-        }
+            LOGGING_SUPPRESSOR.error("Can't open", 3, "Error opening source data line", e);
+            mRunning = false;
 
-        updateToneInsertionAudioClips();
-
-        //Register to receive preference update notifications so we can update the preference items
-        MyEventBus.getGlobalEventBus().register(this);
-    }
-
-    /**
-     * Indicates if this audio output doesn't currently have any audio segments queued for playback.
-     * @return true if empty
-     */
-    public boolean isEmpty()
-    {
-        return mAudioSegmentQueue.isEmpty();
-    }
-
-    /**
-     * Schedules the audio segment for playback.  The audio segment user count should already be incremented by the
-     * calling entity.
-     *
-     * @param audioSegment to schedule for playback.
-     */
-    public void play(AudioSegment audioSegment)
-    {
-        if(audioSegment != null)
-        {
-            //Audio segment use count has already been incremented by the external caller.
-            mAudioSegmentQueue.add(audioSegment);
-        }
-    }
-
-    /**
-     * Indicates if the audio segment is linked to the current playback audio segment
-     */
-    public boolean isLinkedTo(AudioSegment audioSegment)
-    {
-        return audioSegment.isLinked() && audioSegment.isLinkedTo(mCurrentAudioSegment);
-    }
-
-    /**
-     * Receive and process audio identifier update notifications.
-     */
-    @Override
-    public void receive(IdentifierUpdateNotification identifierUpdateNotification)
-    {
-        if(mCurrentAudioSegment != null)
-        {
-            IdentifierCollection identifierCollection = mCurrentAudioSegment.getIdentifierCollection();
-
-            if(identifierCollection != null)
+            for(AudioChannel audioChannel: mAudioProvider.getAudioChannels())
             {
-                broadcast(identifierCollection);
+                audioChannel.setDisabled(true);
             }
         }
     }
 
     /**
-     * Guava event bus notifications that the preferences have been updated, so that we can update audio segment tones.
+     * Plays the test audio over the selected audio channel(s)
+     * @param request to play test audio
      */
-    @Subscribe
-    public void preferenceUpdated(PreferenceType preferenceType)
+    public void playTestAudio(PlayTestAudioRequest request)
     {
-        if(preferenceType == PreferenceType.PLAYBACK)
+        //If we're not running, resize the audio samples to fill the buffer enough to trigger playback.
+        float[] audio = mRunning ? request.audio() : Arrays.copyOf(request.audio(), BUFFER_SIZE_SAMPLES);
+
+        List<AudioChannel> channels = mAudioProvider.getAudioChannels();
+
+        if(request.isAllChannels())
         {
-            updateToneInsertionAudioClips();
-        }
-        else if(preferenceType == PreferenceType.DUPLICATE_CALL_DETECTION)
-        {
-            mDropDuplicates = mUserPreferences.getCallManagementPreference().isDuplicatePlaybackSuppressionEnabled();
-        }
-    }
-
-    /**
-     * Updates audio segment start, drop and preempt tone insertion clips
-     */
-    private void updateToneInsertionAudioClips()
-    {
-        mAudioSegmentStartTone = null;
-        mAudioSegmentDropTone = null;
-
-        float[] start = mUserPreferences.getPlaybackPreference().getStartTone();
-
-        if(start != null)
-        {
-            mAudioSegmentStartTone = convert(start);
-        }
-
-        float[] drop = mUserPreferences.getPlaybackPreference().getDropTone();
-
-        if(drop != null)
-        {
-            mAudioSegmentDropTone = convert(drop);
-        }
-    }
-
-    /**
-     * Writes the audio buffer data to the source data line.  If the data line is not currently playing, write as
-     * much of the buffer to the data line as will fit, start the dataline, and then finish writing the residual
-     * buffer content to the data line as a blocking call.
-     *
-     * @param buffer of audio to playback
-     */
-    private void playAudio(ByteBuffer buffer)
-    {
-        if(mOutput == null)
-        {
-            LOGGING_SUPPRESSOR.error("null output", 2, "Audio Output is null - ignoring audio playback request");
-            return;
-        }
-
-        if(buffer != null && buffer.array().length > 0)
-        {
-            int wrote = 0;
-
-            //If the output data line is not running, we can only write up to the available capacity.  So, only write
-            //what will fit initially, start playback, and then use a blocking write for the remainder.
-            if(!mOutput.isRunning())
+            for(AudioChannel channel : channels)
             {
-                int toWrite = mOutput.available();
-
-                if(toWrite > buffer.array().length)
-                {
-                    toWrite = buffer.array().length;
-                }
-
-                //Top off the buffer and check if we can start it
-                wrote += mOutput.write(buffer.array(), 0, toWrite);
-                mOutputLastTimestamp = System.currentTimeMillis();
-
-                checkStart();
-
-                //Something is causing the source data line to fail to accept audio byte data via the write() method
-                //and this seems to have started around JDK22, maybe.  When this happens, close and then re-open the
-                //data line to clear the error state.  Note: in testing this error condition, the line is showing
-                //the buffer is empty and the capacity is fully available, so it should have accepted attempts to write
-                //data, but it failed, as indicated by wrote=0.
-                if(!mOutput.isRunning() && wrote <= 0)
-                {
-                    mOutput.close();
-
-                    try
-                    {
-                        mOutput.open();
-                    }
-                    catch(Exception e)
-                    {
-                        mLog.error("Error after closing and attempting to reopen audio output", e);
-                    }
-                }
-            }
-
-            if(mOutput.isRunning() && wrote < buffer.array().length)
-            {
-                //This will block until the buffer is fully written to the data line
-                mOutput.write(buffer.array(), wrote, buffer.array().length - wrote);
-                mOutputLastTimestamp = System.currentTimeMillis();
+                channel.playTest(audio);
             }
         }
-    }
-
-    /**
-     * Dispose of the currently assigned audio segment.
-     */
-    private void disposeCurrentAudioSegment()
-    {
-        if(mCurrentAudioSegment != null)
+        else if(request.channel() < channels.size())
         {
-            mCurrentAudioSegment.decrementConsumerCount();
-            mCurrentAudioSegment.removeIdentifierUpdateNotificationListener(this);
-            mCurrentAudioSegment = null;
-            broadcast(null);
+            channels.get(request.channel()).playTest(audio);
+        }
+        else if(!channels.isEmpty())
+        {
+            channels.getFirst().playTest(audio);
+        }
+        else
+        {
+            LOGGING_SUPPRESSOR.info("No Audio Channels", 2,
+                    "Unable to play test audio - no audio channels configured currently");
         }
     }
 
     /**
-     * Loads the next audio segment from the queue.
+     * Audio playback device descriptor for this audio output
      */
-    private void loadNextAudioSegment()
+    public AudioPlaybackDeviceDescriptor getAudioPlaybackDeviceDescriptor()
     {
-        AudioSegment audioSegment = mAudioSegmentQueue.poll();
-
-        boolean verificationInProgress = (audioSegment != null);
-
-        while(verificationInProgress)
-        {
-            if(audioSegment != null)
-            {
-                //Throw away the audio segment if it has been flagged as do not monitor or is duplicate
-                if(isThrowaway(audioSegment))
-                {
-                    audioSegment.decrementConsumerCount();
-                    audioSegment = mAudioSegmentQueue.poll();
-                }
-                else
-                {
-                    verificationInProgress = false;
-                }
-            }
-            else
-            {
-                verificationInProgress = false;
-            }
-        }
-
-        mCurrentAudioSegment = audioSegment;
-
-        if(audioSegment != null)
-        {
-            mCurrentAudioSegment.addIdentifierUpdateNotificationListener(this);
-            broadcast(mCurrentAudioSegment.getIdentifierCollection());
-        }
-
-        mCurrentBufferIndex = 0;
+        return mAudioPlaybackDeviceDescriptor;
     }
 
     /**
-     * Indicates if the audio segment should be thrown away because it is marked as duplicate or do-not-monitor.
-     * @param audioSegment to evaluate
-     * @return true if the audio should be thrown away.
+     * Audio provider managed by this audio output
      */
-    private boolean isThrowaway(AudioSegment audioSegment)
+    public AudioProvider getAudioProvider()
     {
-        return audioSegment != null && (audioSegment.isDoNotMonitor() || mDropDuplicates && (audioSegment.isDuplicate()));
+        return mAudioProvider;
     }
 
     /**
-     * Manage audio segment playback and process audio segment buffers.  This method is designed to be called
-     * by a threaded processor repeatedly to playback the current audio segment and check for and start newly
-     * added audio segments.  It also handles starting and stopping the playback source data line to avoid audio
-     * discontinuities due to buffer underruns.
+     * Process audio from the audio provider and writes it to the mixer's source data line.  Calls to this method can
+     * block on the source data line until it has capacity available to accept the audio.
      */
     private void processAudio()
     {
-        if(mCurrentAudioSegment == null)
+        if(mSourceDataLine == null)
         {
-            loadNextAudioSegment();
+            LOGGING_SUPPRESSOR.error("null output", 2,
+                    "Audio Output source data line is null - ignoring audio playback request");
+            return;
         }
 
-        //Evaluate current audio segment to see if the status has changed for duplicate or do-not-monitor.
-        while(isThrowaway(mCurrentAudioSegment))
+        ByteBuffer buffer = mAudioProvider.getAudio();
+
+        if(buffer != null)
         {
-            if(mCurrentBufferIndex > 0)
+            //This is a blocking method call.
+            int wrote = mSourceDataLine.write(buffer.array(), 0, buffer.array().length);
+
+            //Around JDK 22 something started causing the source data line to fail to accept audio byte data via the
+            //write() method. When this happens, close and reopen the data line to clear the error state.
+            if(wrote <= 0)
             {
-                playAudio(mAudioSegmentDropTone);
-            }
-
-            disposeCurrentAudioSegment();
-            loadNextAudioSegment();
-        }
-
-        while(mCurrentAudioSegment != null && mCurrentBufferIndex < mCurrentAudioSegment.getAudioBufferCount())
-        {
-            //Continuously evaluate current audio segment to see if the status has changed for duplicate or do-not-monitor.
-            if(isThrowaway(mCurrentAudioSegment))
-            {
-                if(mCurrentBufferIndex > 0)
-                {
-                    playAudio(mAudioSegmentDropTone);
-                }
-
-                disposeCurrentAudioSegment();
-            }
-            else
-            {
-                if(mCurrentBufferIndex == 0)
-                {
-                    playAudio(mAudioSegmentStartTone);
-                }
-
-                try
-                {
-                    float[] audioBuffer = mCurrentAudioSegment.getAudioBuffers().get(mCurrentBufferIndex++);
-
-                    if(audioBuffer != null)
-                    {
-                        ByteBuffer audio = convert(audioBuffer);
-                        //This call blocks until all audio bytes are dumped into the data line.
-                        playAudio(audio);
-                    }
-                }
-                catch(Exception e)
-                {
-                    mLog.error("Error while processing audio for [" + mMixerChannel.name() + "]", e);
-                }
+                LOGGING_SUPPRESSOR.info("Stalled Data Line", 3,
+                        "Audio playback data line has stopped accepting samples - recycling to clear the error");
+                mSourceDataLine.close();
+                openSourceDataLine();
             }
         }
-
-        //Check for completed and fully-played audio segment to closeout
-        if(mCurrentAudioSegment != null &&
-           mCurrentAudioSegment.isComplete() &&
-           (mCurrentBufferIndex >= mCurrentAudioSegment.getAudioBufferCount()))
-        {
-            disposeCurrentAudioSegment();
-        }
-
-        checkStop();
     }
 
     /**
@@ -475,156 +262,30 @@ public abstract class AudioOutput implements LineListener, Listener<IdentifierUp
      */
     public void dispose()
     {
-        MyEventBus.getGlobalEventBus().unregister(this);
-        mCanProcessAudio = false;
-
         if(mProcessorFuture != null)
         {
             mProcessorFuture.cancel(true);
         }
-
         mProcessorFuture = null;
-        disposeCurrentAudioSegment();
-        mAudioEventBroadcaster.clear();
-        mIdentifierCollectionListener = null;
 
-        if(mOutput != null)
+        if(mScheduledExecutorService != null)
         {
-            mOutput.close();
+            mScheduledExecutorService.shutdownNow();
+            mScheduledExecutorService = null;
         }
 
-        mOutput = null;
+        mAudioProvider.dispose();
+        mCanProcessAudio = false;
+
+        if(mSourceDataLine != null)
+        {
+            mSourceDataLine.stop();
+            mSourceDataLine.flush();
+            mSourceDataLine.close();
+        }
+        mSourceDataLine = null;
         mGainControl = null;
-        mMuteControl = null;
-    }
-
-    /**
-     * Converts the audio buffer data into a byte buffer format appropriate for the underlying source data line.
-     */
-    protected abstract ByteBuffer convert(float[] buffer);
-
-    /**
-     * Audio output channel name
-     */
-    public String getChannelName()
-    {
-        return mMixerChannel.getLabel();
-    }
-
-    /**
-     * Mixer Channel for this audio output
-     */
-    protected MixerChannel getMixerChannel()
-    {
-        return mMixerChannel;
-    }
-
-    /**
-     * Registers a single listener to receive audio start and audio stop events
-     */
-    public void addAudioEventListener(Listener<AudioEvent> listener)
-    {
-        mAudioEventBroadcaster.addListener(listener);
-    }
-
-    public void removeAudioEventListener(Listener<AudioEvent> listener)
-    {
-        mAudioEventBroadcaster.removeListener(listener);
-    }
-
-    /**
-     * Broadcasts an audio event to the registered listener
-     */
-    private void broadcastAudioEvent(AudioEvent audioEvent)
-    {
-        mAudioEventBroadcaster.broadcast(audioEvent);
-    }
-
-    /**
-     * Registers a single listener to receive the audio metadata from each
-     * audio packet
-     */
-    public void setIdentifierCollectionListener(Listener<IdentifierCollection> listener)
-    {
-        mIdentifierCollectionListener = listener;
-    }
-
-    /**
-     * Unregisters the current audio metadata listener
-     */
-    public void removeAudioMetadataListener()
-    {
-        mIdentifierCollectionListener = null;
-    }
-
-    /**
-     * Broadcasts audio identifier collection metadata to the registered listener
-     */
-    private void broadcast(IdentifierCollection identifierCollection)
-    {
-        if(mIdentifierCollectionListener != null)
-        {
-            mIdentifierCollectionListener.receive(identifierCollection);
-        }
-    }
-
-    /**
-     * Starts audio playback once audio buffer is almost full and remaining capacity falls below the start threshold.
-     *
-     * Note: this method should only be invoked from the processAudio() method
-     */
-    private void checkStart()
-    {
-        if(mCanProcessAudio && !mOutput.isRunning() && mOutput.available() <= mBufferStartThreshold)
-        {
-            mOutput.start();
-            mRunning = true;
-        }
-    }
-
-    /**
-     * Stops audio playback and drains the audio buffer to empty when the audio buffer is mostly empty and the
-     * available buffer capacity exceeds the stop threshold
-     *
-     * Note: this method should only be invoked from the processAudio() method
-     */
-    private void checkStop()
-    {
-        if(mRunning)
-        {
-            //If the output buffer falls below the threshold then drain the output and stop playback
-            if(mOutput.isRunning())
-            {
-                if(mOutput.available() >= mBufferStopThreshold)
-                {
-                    mOutput.drain();
-                    mOutput.stop();
-                    mRunning = false;
-                }
-                //Detect when we have a partially filled output that will neither start nor stop and the last write
-                //timestamp was more than the staleness threshold (500 ms) -- stop the output and discard stale contents
-                else if(mOutput.available() < mBufferStopThreshold &&
-                        mOutput.available() > mBufferStartThreshold &&
-                        (System.currentTimeMillis() - mOutputLastTimestamp >= STALE_PLAYBACK_THRESHOLD_MS))
-                {
-                    mOutput.stop();
-                    //Discard the stale buffer contents.
-                    mOutput.flush();
-                    mRunning = false;
-                }
-            }
-            //If output playback stopped on its own because the buffer emptied, then cleanup
-            else
-            {
-                mRunning = false;
-            }
-
-            //If we stopped audio playback, broadcast a null identifier to clear the gui panel
-            if(!mRunning)
-            {
-                broadcast(null);
-            }
-        }
+        mRunning = false;
     }
 
     /**
@@ -632,11 +293,13 @@ public abstract class AudioOutput implements LineListener, Listener<IdentifierUp
      */
     public void setMuted(boolean muted)
     {
-        if(mMuteControl != null)
+        for(AudioChannel audioChannel: mAudioProvider.getAudioChannels())
         {
-            mMuteControl.setValue(muted);
-            broadcastAudioEvent(new AudioEvent(muted ? AudioEvent.Type.AUDIO_MUTED : AudioEvent.Type.AUDIO_UNMUTED, getChannelName()));
+            audioChannel.setMuted(muted);
         }
+
+        AudioEvent.Type type = muted ? AudioEvent.Type.AUDIO_MUTED : AudioEvent.Type.AUDIO_UNMUTED;
+        mAudioProvider.notify(type);
     }
 
     /**
@@ -644,9 +307,9 @@ public abstract class AudioOutput implements LineListener, Listener<IdentifierUp
      */
     public boolean isMuted()
     {
-        if(mMuteControl != null)
+        if(!mAudioProvider.getAudioChannels().isEmpty())
         {
-            return mMuteControl.getValue();
+            return mAudioProvider.getAudioChannels().getFirst().isMuted();
         }
 
         return false;
@@ -679,20 +342,20 @@ public abstract class AudioOutput implements LineListener, Listener<IdentifierUp
 
         if(type == LineEvent.Type.START)
         {
-            mAudioEventBroadcaster.broadcast(mAudioStartEvent);
+            mAudioProvider.notify(AudioEvent.Type.AUDIO_STARTED);
         }
         else if(type == LineEvent.Type.STOP)
         {
-            mAudioEventBroadcaster.broadcast(mAudioStopEvent);
+            mAudioProvider.notify(AudioEvent.Type.AUDIO_STOPPED);
         }
     }
 
     /**
-     * Runnable audio segment processor
+     * Audio Processor thread
      */
-    public class AudioSegmentProcessor implements Runnable
+    public class AudioProcessor implements Runnable
     {
-        private AtomicBoolean mProcessing = new AtomicBoolean();
+        private final AtomicBoolean mProcessing = new AtomicBoolean();
 
         @Override
         public void run()

src/main/java/io/github/dsheirer/audio/playback/AudioPanel.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -20,8 +20,6 @@ package io.github.dsheirer.audio.playback;
 
 import io.github.dsheirer.alias.AliasModel;
 import io.github.dsheirer.audio.AudioEvent;
-import io.github.dsheirer.audio.AudioException;
-import io.github.dsheirer.audio.IAudioController;
 import io.github.dsheirer.eventbus.MyEventBus;
 import io.github.dsheirer.gui.preference.PreferenceEditorType;
 import io.github.dsheirer.gui.preference.ViewUserPreferenceEditorRequest;
@@ -29,81 +27,77 @@ import io.github.dsheirer.icon.IconModel;
 import io.github.dsheirer.preference.UserPreferences;
 import io.github.dsheirer.sample.Listener;
 import io.github.dsheirer.settings.SettingsManager;
-import io.github.dsheirer.source.mixer.MixerChannelConfiguration;
+import java.awt.Color;
+import java.awt.EventQueue;
+import java.awt.event.MouseEvent;
+import java.awt.event.MouseListener;
 import jiconfont.icons.font_awesome.FontAwesome;
-import jiconfont.swing.IconFontSwing;
+import io.github.dsheirer.gui.theme.ThemedFontIcon;
 import net.miginfocom.swing.MigLayout;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 import javax.sound.sampled.FloatControl;
 import javax.swing.Icon;
 import javax.swing.ImageIcon;
 import javax.swing.JButton;
-import javax.swing.JMenu;
 import javax.swing.JMenuItem;
-import javax.swing.JOptionPane;
 import javax.swing.JPanel;
 import javax.swing.JPopupMenu;
 import javax.swing.JSlider;
 import javax.swing.SwingUtilities;
-import javax.swing.event.ChangeEvent;
-import javax.swing.event.ChangeListener;
-import java.awt.Color;
-import java.awt.EventQueue;
-import java.awt.event.ActionEvent;
-import java.awt.event.ActionListener;
-import java.awt.event.MouseEvent;
-import java.awt.event.MouseListener;
 
+/**
+ * Audio playback panel
+ */
 public class AudioPanel extends JPanel implements Listener<AudioEvent>
 {
-    private static final long serialVersionUID = 1L;
-
-    private static final Logger mLog = LoggerFactory.getLogger(AudioPanel.class);
-
-    private static ImageIcon MUTED_ICON = IconModel.getScaledIcon("images/audio_muted.png", 20);
-    private static ImageIcon UNMUTED_ICON = IconModel.getScaledIcon("images/audio_unmuted.png", 20);
-
-    private IconModel mIconModel;
-    private SettingsManager mSettingsManager;
-    private IAudioController mController;
-    private AliasModel mAliasModel;
-    private UserPreferences mUserPreferences;
-
-    private JButton mMuteButton;
+    private static final ImageIcon MUTED_ICON = IconModel.getScaledIcon("images/audio_muted.png", 20);
+    private static final ImageIcon UNMUTED_ICON = IconModel.getScaledIcon("images/audio_unmuted.png", 20);
+    private final AliasModel mAliasModel;
+    private final AudioPlaybackManager mAudioPlaybackManager;
+    private final IconModel mIconModel;
+    private final SettingsManager mSettingsManager;
+    private final UserPreferences mUserPreferences;
     private AudioChannelsPanel mAudioChannelsPanel;
+    private JButton mMuteButton;
 
+    /**
+     * Constructs an instance
+     * @param iconModel for icon lookup
+     * @param userPreferences for preference lookup
+     * @param settingsManager to monitor for changes
+     * @param audioPlaybackManager for accessing the audio output
+     * @param aliasModel for alias lookup
+     */
     public AudioPanel(IconModel iconModel, UserPreferences userPreferences, SettingsManager settingsManager,
-                      IAudioController controller, AliasModel aliasModel)
+                      AudioPlaybackManager audioPlaybackManager, AliasModel aliasModel)
     {
         mIconModel = iconModel;
         mSettingsManager = settingsManager;
-        mController = controller;
+        mAudioPlaybackManager = audioPlaybackManager;
         mAliasModel = aliasModel;
         mUserPreferences = userPreferences;
-
-        mController.addControllerListener(this);
-
+        mAudioPlaybackManager.addAudioEventListener(this);
         init();
     }
 
+    /**
+     * Initialize the display
+     */
     private void init()
     {
         setLayout(new MigLayout("insets 0 0 0 0", "[]0[grow,fill]", "[fill]0[]"));
         setBackground(Color.BLACK);
-
         mMuteButton = new MuteButton();
         mMuteButton.setBackground(getBackground());
         add(mMuteButton);
-
-        mAudioChannelsPanel = new AudioChannelsPanel(mIconModel, mUserPreferences, mSettingsManager, mController, mAliasModel);
-
+        mAudioChannelsPanel = new AudioChannelsPanel(mIconModel, mUserPreferences, mSettingsManager, mAudioPlaybackManager, mAliasModel);
         add(mAudioChannelsPanel);
-
         addMouseListener(new MouseSelectionListener());
     }
 
+    /**
+     * Receive audio event notifications from the audio playback controller
+     */
     @Override
     public void receive(AudioEvent event)
     {
@@ -112,19 +106,14 @@ public class AudioPanel extends JPanel implements Listener<AudioEvent>
             case AUDIO_CONFIGURATION_CHANGE_STARTED:
                 break;
             case AUDIO_CONFIGURATION_CHANGE_COMPLETE:
-                EventQueue.invokeLater(new Runnable()
-                {
-                    @Override
-                    public void run()
-                    {
-                        remove(mAudioChannelsPanel);
-                        mAudioChannelsPanel.dispose();
-                        mAudioChannelsPanel = new AudioChannelsPanel(mIconModel, mUserPreferences, mSettingsManager, mController, mAliasModel);
-                        add(mAudioChannelsPanel);
-                        mAudioChannelsPanel.repaint();
-                        revalidate();
-                        repaint();
-                    }
+                EventQueue.invokeLater(() -> {
+                    remove(mAudioChannelsPanel);
+                    mAudioChannelsPanel.dispose();
+                    mAudioChannelsPanel = new AudioChannelsPanel(mIconModel, mUserPreferences, mSettingsManager, mAudioPlaybackManager, mAliasModel);
+                    add(mAudioChannelsPanel);
+                    mAudioChannelsPanel.repaint();
+                    revalidate();
+                    repaint();
                 });
                 break;
             default:
@@ -135,26 +124,19 @@ public class AudioPanel extends JPanel implements Listener<AudioEvent>
     /**
      * Audio output mute control menu item.
      */
-    public class AudioOutputMuteItem extends JMenuItem
+    public static class AudioOutputMuteItem extends JMenuItem
     {
-        private static final long serialVersionUID = 1L;
-
-        private AudioOutput mAudioOutput;
+        private final AudioOutput mAudioOutput;
 
+        /**
+         * Constructs an instance
+         * @param audioOutput to mute/unmute
+         */
         public AudioOutputMuteItem(AudioOutput audioOutput)
         {
             super(audioOutput.isMuted() ? "Unmute" : "Mute");
-
             mAudioOutput = audioOutput;
-
-            addActionListener(new ActionListener()
-            {
-                @Override
-                public void actionPerformed(ActionEvent e)
-                {
-                    mAudioOutput.setMuted(!mAudioOutput.isMuted());
-                }
-            });
+            addActionListener(e -> mAudioOutput.setMuted(!mAudioOutput.isMuted()));
         }
     }
 
@@ -169,37 +151,23 @@ public class AudioPanel extends JPanel implements Listener<AudioEvent>
             if(SwingUtilities.isRightMouseButton(event))
             {
                 JPopupMenu popup = new JPopupMenu();
-
-				/* Audio mixer/output selection menus */
-                JMenuItem outputMenu = new JMenuItem("Configure ...");
-                Icon icon = IconFontSwing.buildIcon(FontAwesome.COG, 14);
+                JMenuItem outputMenu = new JMenuItem("Audio Playback Device ...");
+                Icon icon = new ThemedFontIcon(FontAwesome.COG, 14);
                 outputMenu.setIcon(icon);
-                outputMenu.addActionListener(new ActionListener()
-                {
-                    @Override
-                    public void actionPerformed(ActionEvent e)
-                    {
-                        MyEventBus.getGlobalEventBus().post(new ViewUserPreferenceEditorRequest(PreferenceEditorType.AUDIO_OUTPUT));
-                    }
-                });
+                outputMenu.addActionListener(e -> MyEventBus.getGlobalEventBus()
+                        .post(new ViewUserPreferenceEditorRequest(PreferenceEditorType.AUDIO_OUTPUT)));
                 popup.add(outputMenu);
-                popup.add(new JPopupMenu.Separator());
 
-				/* Audio output mute and volume control */
-                for(AudioOutput output : mController.getAudioOutputs())
+                //Add optional gain controller for th eaudio output
+                if(mAudioPlaybackManager.getAudioOutput() != null && mAudioPlaybackManager.getAudioOutput().hasGainControl())
                 {
-                    JMenu menu = new JMenu("Channel: " + output.getChannelName());
-
-                    menu.add(new AudioOutputMuteItem(output));
-
-                    if(output.hasGainControl())
-                    {
-                        JMenu volume = new JMenu("Volume");
-                        volume.add(new VolumeSlider(output.getGainControl()));
-                        menu.add(volume);
-                    }
-
-                    popup.add(menu);
+                    popup.add(new JPopupMenu.Separator());
+                    JMenuItem volume = new JMenuItem("Audio Volume");
+                    volume.setEnabled(false);
+                    Icon volumeIcon = new ThemedFontIcon(FontAwesome.VOLUME_UP, 14);
+                    volume.setIcon(volumeIcon);
+                    popup.add(volume);
+                    popup.add(new VolumeSlider(mAudioPlaybackManager.getAudioOutput().getGainControl()));
                 }
 
                 popup.show(event.getComponent(), event.getX(), event.getY());
@@ -230,12 +198,14 @@ public class AudioPanel extends JPanel implements Listener<AudioEvent>
     /**
      * Audio volume (gain) adjustment slider control
      */
-    public class VolumeSlider extends JSlider
+    public static class VolumeSlider extends JSlider
     {
-        private static final long serialVersionUID = 1L;
-
-        private FloatControl mFloatControl;
+        private final FloatControl mFloatControl;
 
+        /**
+         * Constructs an instance
+         * @param control to be controlled
+         */
         public VolumeSlider(FloatControl control)
         {
             super(0, 100, 0);
@@ -244,21 +214,11 @@ public class AudioPanel extends JPanel implements Listener<AudioEvent>
             setMinorTickSpacing(5);
             setPaintTicks(true);
             setPaintLabels(true);
-
             mFloatControl = control;
-
             setValue(getIntegerValue(mFloatControl.getValue()));
-
-            addChangeListener(new ChangeListener()
-            {
-                @Override
-                public void stateChanged(ChangeEvent event)
-                {
-                    mFloatControl.shift(mFloatControl.getValue(),
-                        getFloatValue(VolumeSlider.this.getValue()),
-                        1000);
-                }
-            });
+            addChangeListener(event -> mFloatControl.shift(mFloatControl.getValue(),
+                getFloatValue(VolumeSlider.this.getValue()),
+                1000));
 
             addMouseListener(new MouseListener()
             {
@@ -270,22 +230,10 @@ public class AudioPanel extends JPanel implements Listener<AudioEvent>
                         VolumeSlider.this.setValue(50);
                     }
                 }
-
-                public void mouseReleased(MouseEvent arg0)
-                {
-                }
-
-                public void mousePressed(MouseEvent arg0)
-                {
-                }
-
-                public void mouseExited(MouseEvent arg0)
-                {
-                }
-
-                public void mouseEntered(MouseEvent arg0)
-                {
-                }
+                public void mouseReleased(MouseEvent arg0) {}
+                public void mousePressed(MouseEvent arg0) {}
+                public void mouseExited(MouseEvent arg0) {}
+                public void mouseEntered(MouseEvent arg0) {}
             });
         }
 
@@ -331,52 +279,12 @@ public class AudioPanel extends JPanel implements Listener<AudioEvent>
         }
     }
 
-    /**
-     * Mixer/Channel configuration selection item
-     */
-    public class MixerSelectionItem extends JMenuItem
-    {
-        private static final long serialVersionUID = 1L;
-
-        private MixerChannelConfiguration mConfiguration;
-
-        public MixerSelectionItem(MixerChannelConfiguration config)
-        {
-            super(config.toString());
-
-            mConfiguration = config;
-
-            addActionListener(new ActionListener()
-            {
-                @Override
-                public void actionPerformed(ActionEvent e)
-                {
-                    try
-                    {
-                        mController.setMixerChannelConfiguration(mConfiguration);
-                    }
-                    catch(AudioException e1)
-                    {
-                        mLog.error("Couldn't set mixer channel configuration "
-                            + "to: " + mConfiguration.toString());
-
-                        JOptionPane.showMessageDialog(MixerSelectionItem.this,
-                            "Couldn't set [" + mConfiguration.toString() +
-                                "] as the audio output device");
-                    }
-                }
-            });
-        }
-    }
-
     /**
      * Mute button to mute all audio output channels exposed by the audio
      * controller
      */
     public class MuteButton extends JButton
     {
-        private static final long serialVersionUID = 1L;
-
         private boolean mMuted = false;
 
         public MuteButton()
@@ -384,29 +292,13 @@ public class AudioPanel extends JPanel implements Listener<AudioEvent>
             setIcon(UNMUTED_ICON);
             setBorderPainted(false);
             getAccessibleContext().setAccessibleName("Mute");
-
-            addActionListener(new ActionListener()
-            {
-                @Override
-                public void actionPerformed(ActionEvent e)
-                {
-                    mMuted = !mMuted;
-
-                    for(AudioOutput output : mController.getAudioOutputs())
-                    {
-                        output.setMuted(mMuted);
-                    }
-
-                    EventQueue.invokeLater(new Runnable()
-                    {
-                        @Override
-                        public void run()
-                        {
-                            setIcon(mMuted ? MUTED_ICON : UNMUTED_ICON);
-                            getAccessibleContext().setAccessibleName(mMuted ? "Unmute" : "Mute");
-                        }
-                    });
-                }
+            addActionListener(e -> {
+                mMuted = !mMuted;
+                mAudioPlaybackManager.getAudioOutput().setMuted(mMuted);
+                EventQueue.invokeLater(() -> {
+                    setIcon(mMuted ? MUTED_ICON : UNMUTED_ICON);
+                    getAccessibleContext().setAccessibleName(mMuted ? "Unmute" : "Mute");
+                });
             });
         }
     }

src/main/java/io/github/dsheirer/audio/playback/AudioPlaybackDeviceDescriptor.java

@@ -0,0 +1,123 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.audio.playback;
+
+import javax.sound.sampled.AudioFormat;
+import javax.sound.sampled.AudioSystem;
+import javax.sound.sampled.Mixer;
+
+/**
+ * Audio playback device descriptor for a mixer and a supported audio output format (ie number of channels).
+ */
+public class AudioPlaybackDeviceDescriptor implements Comparable<AudioPlaybackDeviceDescriptor>
+{
+    private final Mixer.Info mMixerInfo;
+    private final AudioFormat mAudioFormat;
+
+    /**
+     * Constructs an instance
+     *
+     * @param mixerInfo for the mixer
+     * @param audioFormat supported by the mixer
+     */
+    public AudioPlaybackDeviceDescriptor(Mixer.Info mixerInfo, AudioFormat audioFormat)
+    {
+        mMixerInfo = mixerInfo;
+        mAudioFormat = audioFormat;
+    }
+
+    @Override
+    public String toString()
+    {
+        return getCleanDescription(getMixerInfo()) + "(" + getMixerInfo().getName() + ") - " +
+                getChannelDescription(getAudioFormat());
+    }
+
+    /**
+     * Cleans the mixer description to reformat/reword certain mixer descriptions
+     * @param mixerInfo containing a description
+     * @return cleaned description
+     */
+    private static String getCleanDescription(Mixer.Info mixerInfo)
+    {
+        if(mixerInfo.getDescription().contains("Direct Audio Device: "))
+        {
+            return mixerInfo.getDescription().replace("Direct Audio Device: ", "");
+        }
+        else if(mixerInfo.getDescription().contains("alsa_playback.java"))
+        {
+            return "Default (Java/ALSA)";
+        }
+        else
+        {
+            return mixerInfo.getDescription();
+        }
+    }
+
+    /**
+     * Provides a description of the channels for the audio format
+     * @param audioFormat with channels
+     * @return pretty string
+     */
+    private static String getChannelDescription(AudioFormat audioFormat)
+    {
+        return switch(audioFormat.getChannels())
+        {
+            case 1 -> "Mono";
+            case 2 -> "Stereo";
+            case AudioSystem.NOT_SPECIFIED -> "Unknown number of channels";
+            default -> audioFormat.getChannels() + " Channels";
+        };
+    }
+
+    /**
+     * Audio format supported by the mixer
+     *
+     * @return audio format
+     */
+    public AudioFormat getAudioFormat()
+    {
+        return mAudioFormat;
+    }
+
+    /**
+     * Mixer information for the available system mixer.
+     */
+    public Mixer.Info getMixerInfo()
+    {
+        return mMixerInfo;
+    }
+
+    @Override
+    public int compareTo(AudioPlaybackDeviceDescriptor other)
+    {
+        if(other == null)
+        {
+            return 1;
+        }
+
+        if(other.getMixerInfo().getDescription().equals(getMixerInfo().getDescription()))
+        {
+            return Integer.compare(getAudioFormat().getChannels(), other.getAudioFormat().getChannels());
+        }
+
+        return getMixerInfo().getDescription().compareTo(other.getMixerInfo().getDescription());
+    }
+}

src/main/java/io/github/dsheirer/audio/playback/AudioPlaybackDeviceManager.java

@@ -0,0 +1,171 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.audio.playback;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import javax.sound.sampled.AudioFormat;
+import javax.sound.sampled.AudioSystem;
+import javax.sound.sampled.DataLine;
+import javax.sound.sampled.Line;
+import javax.sound.sampled.Mixer;
+
+/**
+ * Audio playback device manager.
+ */
+public class AudioPlaybackDeviceManager
+{
+    /**
+     * Always returns the first available device in the system.
+     */
+    public static AudioPlaybackDeviceDescriptor getDefaultAudioPLaybackDevice()
+    {
+        List<AudioPlaybackDeviceDescriptor> devices = getAudioPlaybackDevices();
+
+        if(!devices.isEmpty())
+        {
+            return devices.getFirst();
+        }
+
+        return null;
+    }
+
+    /**
+     * Finds the matching audio playback device
+     * @param name of the device
+     * @param channels count
+     * @return matching entry or the default playback device.
+     */
+    public static AudioPlaybackDeviceDescriptor getAudioPlaybackDevice(String name, int channels)
+    {
+        for(AudioPlaybackDeviceDescriptor device: getAudioPlaybackDevices())
+        {
+            if(device.getMixerInfo().getName().equals(name) && device.getAudioFormat().getChannels() == channels)
+            {
+                return device;
+            }
+        }
+
+        return getDefaultAudioPLaybackDevice();
+    }
+
+    public static List<AudioPlaybackDeviceDescriptor> getAudioPlaybackDevices()
+    {
+        List<AudioPlaybackDeviceDescriptor> devices = new ArrayList<>();
+
+        Mixer.Info[] mixerInfos = AudioSystem.getMixerInfo();
+
+        for(Mixer.Info mixerInfo : mixerInfos)
+        {
+            Mixer mixer = AudioSystem.getMixer(mixerInfo);
+
+            if(mixer != null)
+            {
+                List<AudioFormat> discoveredFormats = new ArrayList<>();
+
+                for(Line.Info sourceLineInfo : mixer.getSourceLineInfo())
+                {
+                    if(sourceLineInfo instanceof DataLine.Info dataLineInfo)
+                    {
+                        for(AudioFormat audioFormat : dataLineInfo.getFormats())
+                        {
+                            if(!audioFormat.isBigEndian() && audioFormat.getSampleSizeInBits() == 16 &&
+                               !discoveredFormats.contains(audioFormat))
+                            {
+                                if(audioFormat.getChannels() == 1)
+                                {
+                                    if(audioFormat.getSampleRate() == AudioSystem.NOT_SPECIFIED)
+                                    {
+                                        discoveredFormats.add(audioFormat);
+                                        //Modify the format for 8 kHz sample rate
+                                        AudioFormat updatedFormat = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
+                                                8000, 16, audioFormat.getChannels(), audioFormat.getFrameSize(),
+                                                8000, false);
+                                        devices.add(new AudioPlaybackDeviceDescriptor(mixerInfo, updatedFormat));
+                                    }
+                                    else if(audioFormat.getSampleRate() == 8000)
+                                    {
+                                        discoveredFormats.add(audioFormat);
+                                        devices.add(new AudioPlaybackDeviceDescriptor(mixerInfo, audioFormat));
+                                    }
+                                }
+                                //Stereo and 64-channel formats
+                                else if(audioFormat.getChannels() == 2 || audioFormat.getChannels() > 8)
+                                {
+                                    if(audioFormat.getSampleRate() == AudioSystem.NOT_SPECIFIED)
+                                    {
+                                        discoveredFormats.add(audioFormat);
+                                        //Modify the format for 8 kHz sample rate, 2 channels, 4 bytes per frame
+                                        AudioFormat updatedFormat = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
+                                                8000, 16, 2, 4,
+                                                8000, false);
+                                        devices.add(new AudioPlaybackDeviceDescriptor(mixerInfo, updatedFormat));
+                                    }
+                                    else if(audioFormat.getSampleRate() == 8000)
+                                    {
+                                        discoveredFormats.add(audioFormat);
+                                        //Modify the format for 8 kHz sample rate, 2 channels, 4 bytes per frame
+                                        AudioFormat updatedFormat = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
+                                                audioFormat.getSampleRate(), 16, 2, 4,
+                                                audioFormat.getFrameRate(), false);
+                                        devices.add(new AudioPlaybackDeviceDescriptor(mixerInfo, updatedFormat));
+                                    }
+                                }
+                                //TODO: remove the 2 channels max restriction once supported
+//                                else if(audioFormat.getChannels() > 2 && audioFormat.getChannels() <= 8)
+//                                {
+//                                    if(audioFormat.getSampleRate() == AudioSystem.NOT_SPECIFIED)
+//                                    {
+//                                        discoveredFormats.add(audioFormat);
+//                                        //Modify the format for 8 kHz sample rate
+//                                        AudioFormat updatedFormat = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
+//                                                8000, 16, audioFormat.getChannels(), audioFormat.getFrameSize(),
+//                                                8000, false);
+//                                        devices.add(new AudioPlaybackDeviceDescriptor(mixerInfo, updatedFormat));
+//                                    }
+//                                    else if(audioFormat.getSampleRate() == 8000)
+//                                    {
+//                                        discoveredFormats.add(audioFormat);
+//                                        devices.add(new AudioPlaybackDeviceDescriptor(mixerInfo, audioFormat));
+//                                    }
+//                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+
+        Collections.sort(devices);
+        return devices;
+    }
+
+
+    static void main()
+    {
+        List<AudioPlaybackDeviceDescriptor> devices = getAudioPlaybackDevices();
+        for(AudioPlaybackDeviceDescriptor device : devices)
+        {
+            System.out.println(device);
+        }
+    }
+}

src/main/java/io/github/dsheirer/audio/playback/AudioPlaybackManager.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2024 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -27,11 +27,11 @@ import io.github.dsheirer.controller.NamingThreadFactory;
 import io.github.dsheirer.eventbus.MyEventBus;
 import io.github.dsheirer.preference.PreferenceType;
 import io.github.dsheirer.preference.UserPreferences;
+import io.github.dsheirer.preference.playback.PlayTestAudioRequest;
 import io.github.dsheirer.sample.Broadcaster;
 import io.github.dsheirer.sample.Listener;
-import io.github.dsheirer.source.mixer.MixerChannel;
-import io.github.dsheirer.source.mixer.MixerChannelConfiguration;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.Iterator;
 import java.util.List;
@@ -51,23 +51,16 @@ import org.slf4j.LoggerFactory;
 public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioController
 {
     private static final Logger mLog = LoggerFactory.getLogger(AudioPlaybackManager.class);
-
-    public static final AudioEvent CONFIGURATION_CHANGE_STARTED =
-        new AudioEvent(AudioEvent.Type.AUDIO_CONFIGURATION_CHANGE_STARTED, null);
-    public static final AudioEvent CONFIGURATION_CHANGE_COMPLETE =
-        new AudioEvent(AudioEvent.Type.AUDIO_CONFIGURATION_CHANGE_COMPLETE, null);
-    private Broadcaster<AudioEvent> mControllerBroadcaster = new Broadcaster<>();
+    private final AudioSegmentPrioritySorter mAudioSegmentPrioritySorter = new AudioSegmentPrioritySorter();
+    private final Broadcaster<AudioEvent> mControllerBroadcaster = new Broadcaster<>();
+    private final List<AudioSegment> mAudioSegments = new ArrayList<>();
+    private final List<AudioSegment> mPendingAudioSegments = new ArrayList<>();
+    private final LinkedTransferQueue<AudioSegment> mNewAudioSegmentQueue = new LinkedTransferQueue<>();
+    private final ReentrantLock mAudioChannelsLock = new ReentrantLock();
+    private final UserPreferences mUserPreferences;
+    private AudioPlaybackDeviceDescriptor mAudioPlaybackDevice;
+    private AudioOutput mAudioOutput;
     private ScheduledFuture<?> mProcessingTask;
-    private UserPreferences mUserPreferences;
-    private MixerChannelConfiguration mMixerChannelConfiguration;
-    private List<AudioOutput> mAudioOutputs = new ArrayList<>();
-    private List<AudioSegment> mAudioSegments = new ArrayList<>();
-    private List<AudioSegment> mPendingAudioSegments = new ArrayList<>();
-    private LinkedTransferQueue<AudioSegment> mNewAudioSegmentQueue = new LinkedTransferQueue<>();
-    private ScheduledExecutorService mScheduledExecutorService =
-            Executors.newSingleThreadScheduledExecutor(new NamingThreadFactory("sdrtrunk audio manager"));
-    private AudioSegmentPrioritySorter mAudioSegmentPrioritySorter = new AudioSegmentPrioritySorter();
-    private ReentrantLock mAudioOutputLock = new ReentrantLock();
 
     /**
      * Constructs an instance.
@@ -78,20 +71,18 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
     {
         mUserPreferences = userPreferences;
         MyEventBus.getGlobalEventBus().register(this);
+        AudioPlaybackDeviceDescriptor device = mUserPreferences.getPlaybackPreference().getAudioPlaybackDevice();
 
-        MixerChannelConfiguration configuration = mUserPreferences.getPlaybackPreference().getMixerChannelConfiguration();
-
-        if(configuration != null)
+        if(device != null)
         {
             try
             {
-                setMixerChannelConfiguration(configuration);
+                setAudioPlaybackDevice(device);
             }
             catch(AudioException ae)
             {
-                mLog.error("Error during setup of audio playback configuration.  Attempted to use audio mixer [" +
-                    (configuration != null ? configuration.getMixer().toString() : "null") + "] and channel [" +
-                    (configuration != null ? configuration.getMixerChannel().name() : "null") + "]", ae);
+                mLog.error("Error during setup of audio playback configuration.  Attempted to use device [" +
+                        device + "]", ae);
             }
         }
         else
@@ -99,13 +90,16 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
             mLog.warn("No audio output devices available");
         }
 
-        mProcessingTask = mScheduledExecutorService.scheduleAtFixedRate(new AudioSegmentProcessor(),
+        //Even if we don't have an audio device, setup the queue processor to always process the audio segment queue
+        ScheduledExecutorService scheduledExecutorService =
+                Executors.newSingleThreadScheduledExecutor(new NamingThreadFactory("sdrtrunk audio manager"));
+        mProcessingTask = scheduledExecutorService.scheduleAtFixedRate(new AudioSegmentProcessor(),
                 0, 100, TimeUnit.MILLISECONDS);
     }
 
     /**
      * Receives audio segments from channel audio modules.
-     * @param audioSegment
+     * @param audioSegment to receive and process
      */
     @Override
     public void receive(AudioSegment audioSegment)
@@ -195,42 +189,43 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
                 }
                 else if(audioSegment.isLinked())
                 {
-                    mAudioOutputLock.lock();
-
-                    try
+                    if(mAudioOutput != null)
                     {
-                        for(AudioOutput audioOutput: mAudioOutputs)
+                        mAudioChannelsLock.lock();
+
+                        try
                         {
-                            if(audioOutput.isLinkedTo(audioSegment))
+                            for(AudioChannel audioOutput: mAudioOutput.getAudioProvider().getAudioChannels())
                             {
-                                it.remove();
-                                audioOutput.play(audioSegment);
+                                if(audioOutput.isLinkedTo(audioSegment))
+                                {
+                                    it.remove();
+                                    audioOutput.play(audioSegment);
+                                }
                             }
                         }
-                    }
-                    finally
-                    {
-                        mAudioOutputLock.unlock();
+                        finally
+                        {
+                            mAudioChannelsLock.unlock();
+                        }
                     }
                 }
             }
 
             //Sort audio segments by playback priority and assign to empty audio outputs
-            if(!mAudioSegments.isEmpty())
+            if(!mAudioSegments.isEmpty() && mAudioOutput != null)
             {
                 mAudioSegments.sort(mAudioSegmentPrioritySorter);
-
-                mAudioOutputLock.lock();
+                mAudioChannelsLock.lock();
 
                 try
                 {
                     //Assign empty audio outputs first
-                    for(AudioOutput audioOutput: mAudioOutputs)
+                    for(AudioChannel audioChannel: mAudioOutput.getAudioProvider().getAudioChannels())
                     {
-                        if(audioOutput.isEmpty())
+                        if(audioChannel.isEmpty())
                         {
-                            audioOutput.play(mAudioSegments.remove(0));
-
+                            audioChannel.play(mAudioSegments.removeFirst());
                             if(mAudioSegments.isEmpty())
                             {
                                 return;
@@ -240,7 +235,7 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
                 }
                 finally
                 {
-                    mAudioOutputLock.unlock();
+                    mAudioChannelsLock.unlock();
                 }
             }
 
@@ -273,6 +268,19 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
         mAudioSegments.clear();
     }
 
+    /**
+     * Receives a request from the global event bus to playback a test audio sequence via the specified audio channel
+     * @param request with test audio and channel number
+     */
+    @Subscribe
+    public void playTestAudio(PlayTestAudioRequest request)
+    {
+        if(mAudioOutput != null)
+        {
+            mAudioOutput.playTestAudio(request);
+        }
+    }
+
     /**
      * Receive user preference update notifications so that we can detect when the user changes the audio output
      * device in the user preferences editor.
@@ -282,100 +290,112 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
     {
         if(preferenceType == PreferenceType.PLAYBACK)
         {
-            MixerChannelConfiguration configuration = mUserPreferences.getPlaybackPreference().getMixerChannelConfiguration();
+            AudioPlaybackDeviceDescriptor device = mUserPreferences.getPlaybackPreference().getAudioPlaybackDevice();
 
-            if(configuration != null && !configuration.equals(mMixerChannelConfiguration))
+            if(device != null && !device.equals(getAudioPlaybackDevice()))
             {
                 try
                 {
-                    setMixerChannelConfiguration(configuration);
+                    setAudioPlaybackDevice(device);
                 }
                 catch(AudioException ae)
                 {
-                    mLog.error("Error changing audio output to [" + configuration + "]", ae);
+                    mLog.error("Error changing audio output to [" + device + "]", ae);
                 }
             }
         }
     }
 
     /**
-     * Configures audio playback to use the configuration specified in the entry argument.
+     * Configures audio playback to use the audio device argument.
      *
-     * @param entry to use in configuring the audio playback setup.
+     * @param audioDevice to use in configuring the audio playback setup.
      * @throws AudioException if there is an error
      */
     @Override
-    public void setMixerChannelConfiguration(MixerChannelConfiguration entry) throws AudioException
+    public void setAudioPlaybackDevice(AudioPlaybackDeviceDescriptor audioDevice) throws AudioException
     {
-        if(entry != null)
+        if(audioDevice != null)
         {
-            mControllerBroadcaster.broadcast(CONFIGURATION_CHANGE_STARTED);
+            mControllerBroadcaster.broadcast(new AudioEvent(AudioEvent.Type.AUDIO_CONFIGURATION_CHANGE_STARTED,
+                    audioDevice.getMixerInfo().getName()));
 
-            mAudioOutputLock.lock();
+            mAudioChannelsLock.lock();
 
             try
             {
-                for(AudioOutput audioOutput: mAudioOutputs)
+                if(mAudioOutput != null)
                 {
-                    audioOutput.dispose();
+                    mAudioOutput.dispose();
                 }
 
-                mAudioOutputs.clear();
+                int channelCount = audioDevice.getAudioFormat().getChannels();
 
-                switch(entry.getMixerChannel())
+                switch(channelCount)
                 {
-                    case MONO:
-                        AudioOutput mono = new MonoAudioOutput(entry.getMixer(), mUserPreferences);
-                        mAudioOutputs.add(mono);
+                    case 1:
+                        mAudioOutput = new AudioOutput(audioDevice, new AudioProviderMono(mUserPreferences));
                         break;
-                    case STEREO:
-                        AudioOutput left = new StereoAudioOutput(entry.getMixer(), MixerChannel.LEFT, mUserPreferences);
-                        mAudioOutputs.add(left);
-
-                        AudioOutput right = new StereoAudioOutput(entry.getMixer(), MixerChannel.RIGHT, mUserPreferences);
-                        mAudioOutputs.add(right);
+                    case 2:
+                        mAudioOutput = new AudioOutput(audioDevice, new AudioProviderStereo(mUserPreferences));
                         break;
                     default:
-                        throw new AudioException("Unsupported mixer channel configuration: " + entry.getMixerChannel());
+//                        mAudioOutput = new AudioOutput(audioDevice, new AudioProviderMultiChannel(mUserPreferences,
+//                                audioDevice.getAudioFormat()));
+                        throw new AudioException("Unsupported mixer channel configuration channel count: " + channelCount);
                 }
+
+                //Note: audio output can use an alternate device if the requested device can't be used, so we assign
+                //the descriptor that was actually used by the audio output
+                mAudioPlaybackDevice = mAudioOutput.getAudioPlaybackDeviceDescriptor();
             }
             finally
             {
-                mAudioOutputLock.unlock();
+                mAudioChannelsLock.unlock();
             }
 
-            mControllerBroadcaster.broadcast(CONFIGURATION_CHANGE_COMPLETE);
-            mMixerChannelConfiguration = entry;
+            mControllerBroadcaster.broadcast(new AudioEvent(AudioEvent.Type.AUDIO_CONFIGURATION_CHANGE_COMPLETE,
+                    mAudioPlaybackDevice.getMixerInfo().getName()));
         }
     }
 
+    /**
+     * Audio output device.  Note: this can be null depending on when it is accessed.
+     * @return audio output or null.
+     */
+    public AudioOutput getAudioOutput()
+    {
+        return mAudioOutput;
+    }
+
     /**
      * Current audio playback mixer channel configuration setting.
      */
     @Override
-    public MixerChannelConfiguration getMixerChannelConfiguration()
+    public AudioPlaybackDeviceDescriptor getAudioPlaybackDevice()
     {
-        return mMixerChannelConfiguration;
+        return mAudioPlaybackDevice;
     }
 
     /**
      * List of sorted audio outputs available for the current mixer channel configuration
      */
     @Override
-    public List<AudioOutput> getAudioOutputs()
+    public List<AudioChannel> getAudioChannels()
     {
-        List<AudioOutput> outputs = new ArrayList<>(mAudioOutputs);
+        if(mAudioOutput != null)
+        {
+            return mAudioOutput.getAudioProvider().getAudioChannels();
+        }
 
-        outputs.sort(Comparator.comparing(AudioOutput::getChannelName));
-
-        return outputs;
+        return Collections.emptyList();
     }
 
     /**
      * Adds an audio event listener to receive audio event notifications.
      */
     @Override
-    public void addControllerListener(Listener<AudioEvent> listener)
+    public void addAudioEventListener(Listener<AudioEvent> listener)
     {
         mControllerBroadcaster.addListener(listener);
     }
@@ -384,7 +404,7 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
      * Removes an audio event listener from receiving audio event notifications.
      */
     @Override
-    public void removeControllerListener(Listener<AudioEvent> listener)
+    public void removeAudioEventListener(Listener<AudioEvent> listener)
     {
         mControllerBroadcaster.removeListener(listener);
     }
@@ -394,7 +414,7 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
      */
     public class AudioSegmentProcessor implements Runnable
     {
-        private AtomicBoolean mProcessing = new AtomicBoolean();
+        private final AtomicBoolean mProcessing = new AtomicBoolean();
 
         @Override
         public void run()
@@ -418,7 +438,7 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
     /**
      * Audio segment comparator for sorting audio segments by: 1)Playback priority and 2)Segment start time
      */
-    public class AudioSegmentPrioritySorter implements Comparator<AudioSegment>
+    public static class AudioSegmentPrioritySorter implements Comparator<AudioSegment>
     {
         @Override
         public int compare(AudioSegment segment1, AudioSegment segment2)

src/main/java/io/github/dsheirer/audio/playback/AudioProvider.java

@@ -0,0 +1,72 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.audio.playback;
+
+import io.github.dsheirer.audio.AudioEvent;
+import java.nio.ByteBuffer;
+import java.util.List;
+
+import javax.sound.sampled.AudioFormat;
+
+/**
+ * Abstract audio provider implementation
+ */
+public abstract class AudioProvider
+{
+    /**
+     * Audio format for this provider
+     */
+    public abstract AudioFormat getAudioFormat();
+
+    /**
+     * Provide a non-null, 160-sample/20-millisecond buffer of audio at 8 kHz
+     * @return audio buffer
+     */
+    public abstract ByteBuffer getAudio();
+
+    /**
+     * Provides access to the audio channels for this provider
+     * @return list of audio channels
+     */
+    public abstract List<AudioChannel> getAudioChannels();
+
+    /**
+     * Notifies audio event listener(s) of the event
+     * @param eventType to broadcast
+     */
+    public void notify(AudioEvent.Type eventType)
+    {
+        for(AudioChannel audioChannel : getAudioChannels())
+        {
+            audioChannel.notify(eventType);
+        }
+    }
+
+    /**
+     * Disposes the audio channel to prepare for audio output changes or shutdown.
+     */
+    public void dispose()
+    {
+        for(AudioChannel audioChannel: getAudioChannels())
+        {
+            audioChannel.dispose();
+        }
+    }
+}

src/main/java/io/github/dsheirer/audio/playback/AudioProviderMono.java

@@ -0,0 +1,85 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.audio.playback;
+
+import io.github.dsheirer.audio.AudioFormats;
+import io.github.dsheirer.preference.UserPreferences;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.ShortBuffer;
+import java.util.List;
+
+import javax.sound.sampled.AudioFormat;
+
+/**
+ * Single channel (mono) audio provider wraps a single audio channel and provides converted audio.
+ */
+public class AudioProviderMono extends AudioProvider
+{
+    private static final ByteBuffer SILENCE = ByteBuffer.allocate(AudioChannel.SAMPLES_PER_INTERVAL * 2);
+    private final AudioChannel mAudioChannel;
+
+    /**
+     * Constructs an instance
+     * @param userPreferences for monitoring preference changes
+     */
+    public AudioProviderMono(UserPreferences userPreferences)
+    {
+        mAudioChannel = new AudioChannel(userPreferences, "MONO");
+    }
+
+    @Override
+    public List<AudioChannel> getAudioChannels()
+    {
+        return List.of(mAudioChannel);
+    }
+
+    @Override
+    public AudioFormat getAudioFormat()
+    {
+        return AudioFormats.PCM_SIGNED_8000_HZ_16_BIT_MONO;
+    }
+
+    @Override
+    public ByteBuffer getAudio()
+    {
+        float[] audio = mAudioChannel.getAudio();
+
+        if(audio == null)
+        {
+            if(!mAudioChannel.hasAudioSegment())
+            {
+                mAudioChannel.clearMetadata();
+            }
+
+            return SILENCE;
+        }
+
+        ByteBuffer buffer = ByteBuffer.allocate(AudioChannel.SAMPLES_PER_INTERVAL * 2).order(ByteOrder.LITTLE_ENDIAN);
+        ShortBuffer shortBuffer = buffer.asShortBuffer();
+
+        for(int x = 0; x < AudioChannel.SAMPLES_PER_INTERVAL; x++)
+        {
+            shortBuffer.put((short) (audio[x] * Short.MAX_VALUE));
+        }
+
+        return buffer;
+    }
+}

src/main/java/io/github/dsheirer/audio/playback/AudioProviderMultiChannel.java

@@ -0,0 +1,123 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.audio.playback;
+
+import io.github.dsheirer.preference.UserPreferences;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.ShortBuffer;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import javax.sound.sampled.AudioFormat;
+
+/**
+ * Multi-Channel audio provider implementation.  Provides an interleaved stream of audio from multiple channels.
+ *
+ * Note: this implementation has not been tested for use.
+ */
+public class AudioProviderMultiChannel extends AudioProvider
+{
+    private static ByteBuffer SILENCE;
+    private final List<AudioChannel> mAudioChannels = new ArrayList<>();
+    private final AudioFormat mAudioFormat;
+
+    /**
+     * Constructs a multi-channel audio provider
+     * @param userPreferences for this provider
+     * @param audioFormat for this provider
+     */
+    public AudioProviderMultiChannel(UserPreferences userPreferences, AudioFormat audioFormat)
+    {
+        SILENCE = ByteBuffer.allocate(AudioChannel.SAMPLES_PER_INTERVAL * audioFormat.getChannels());
+
+        for(int channel = 0; channel < audioFormat.getChannels(); channel++)
+        {
+            mAudioChannels.add(new AudioChannel(userPreferences, String.valueOf(channel)));
+        }
+
+        mAudioFormat = audioFormat;
+    }
+
+    @Override
+    public AudioFormat getAudioFormat()
+    {
+        return mAudioFormat;
+    }
+
+    /**
+     * Access the next buffer of audio.
+     * @return next buffer or null if there is no audio available
+     */
+    @Override
+    public ByteBuffer getAudio()
+    {
+        float[][] samples = new float[mAudioChannels.size()][];
+        boolean hasAudio = false;
+
+        AudioChannel channel = null;
+
+        for(int x = 0; x < mAudioChannels.size(); x++)
+        {
+            channel = mAudioChannels.get(x);
+            samples[x] = channel.getAudio();
+
+            if(samples[x] == null)
+            {
+                if(!channel.hasAudioSegment())
+                {
+                    channel.clearMetadata();
+                }
+
+                samples[x] = new float[AudioChannel.SAMPLES_PER_INTERVAL];
+            }
+            else
+            {
+                hasAudio = true;
+            }
+        }
+
+        if(!hasAudio)
+        {
+            return SILENCE;
+        }
+
+        ByteBuffer buffer = ByteBuffer.allocate(AudioChannel.SAMPLES_PER_INTERVAL * 2 *
+                mAudioChannels.size()).order(ByteOrder.LITTLE_ENDIAN);
+        ShortBuffer shortBuffer = buffer.asShortBuffer();
+
+        for(int sampleCounter = 0; sampleCounter < AudioChannel.SAMPLES_PER_INTERVAL; sampleCounter++)
+        {
+            for(int channelNumber = 0; channelNumber < mAudioChannels.size(); channelNumber++)
+            {
+                shortBuffer.put((short)(samples[channelNumber][sampleCounter] * Short.MAX_VALUE));
+            }
+        }
+
+        return buffer;
+    }
+
+    @Override
+    public List<AudioChannel> getAudioChannels()
+    {
+        return Collections.unmodifiableList(mAudioChannels);
+    }
+}

src/main/java/io/github/dsheirer/audio/playback/AudioProviderStereo.java

@@ -0,0 +1,111 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.audio.playback;
+
+import io.github.dsheirer.audio.AudioFormats;
+import io.github.dsheirer.preference.UserPreferences;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.ShortBuffer;
+import java.util.List;
+
+import javax.sound.sampled.AudioFormat;
+
+/**
+ * Provides an interleaved stream of left and right audio samples from audio channels.
+ *
+ * Note: the getAudio() method is optimized to provide buffers of 160 samples (x2) of audio per interval, equivalent to
+ * 20 milliseconds of audio at 8,000 Hertz sample rate.
+ */
+public class AudioProviderStereo extends AudioProvider
+{
+    private final AudioChannel mAudioChannelLeft;
+    private final AudioChannel mAudioChannelRight;
+    private static final ByteBuffer SILENCE = ByteBuffer.allocate(AudioChannel.SAMPLES_PER_INTERVAL * 4);
+
+    /**
+     * Constructs an instance.
+     * @param userPreferences for monitoring preference changes
+     */
+    public AudioProviderStereo(UserPreferences userPreferences)
+    {
+        mAudioChannelLeft = new AudioChannel(userPreferences, "LEFT");
+        mAudioChannelRight = new AudioChannel(userPreferences, "RIGHT");
+    }
+
+    @Override
+    public AudioFormat getAudioFormat()
+    {
+        return AudioFormats.PCM_SIGNED_8000_HZ_16BITS_STEREO;
+    }
+
+    @Override
+    public List<AudioChannel> getAudioChannels()
+    {
+        return List.of(mAudioChannelLeft, mAudioChannelRight);
+    }
+
+    /**
+     * Access the next buffer of audio.
+     * @return next buffer or null if there is no audio available
+     */
+    @Override
+    public ByteBuffer getAudio()
+    {
+        float[] left = mAudioChannelLeft.getAudio();
+
+        if(left == null && !mAudioChannelLeft.hasAudioSegment())
+        {
+            mAudioChannelLeft.clearMetadata();
+        }
+
+        float[] right = mAudioChannelRight.getAudio();
+
+        if(right == null && !mAudioChannelRight.hasAudioSegment())
+        {
+            mAudioChannelRight.clearMetadata();
+        }
+
+        //If we didn't get audio from either channel send silence buffer
+        if(left == null && right == null)
+        {
+            return SILENCE;
+        }
+        else if(left == null)
+        {
+            left = new float[AudioChannel.SAMPLES_PER_INTERVAL];
+        }
+        else if(right == null)
+        {
+            right = new float[AudioChannel.SAMPLES_PER_INTERVAL];
+        }
+
+        ByteBuffer buffer = ByteBuffer.allocate(AudioChannel.SAMPLES_PER_INTERVAL * 4).order(ByteOrder.LITTLE_ENDIAN);
+        ShortBuffer shortBuffer = buffer.asShortBuffer();
+
+        for(int x = 0; x < AudioChannel.SAMPLES_PER_INTERVAL; x++)
+        {
+            shortBuffer.put((short)(left[x] * Short.MAX_VALUE));
+            shortBuffer.put((short)(right[x] * Short.MAX_VALUE));
+        }
+
+        return buffer;
+    }
+}

src/main/java/io/github/dsheirer/audio/playback/MonoAudioOutput.java

@@ -1,65 +0,0 @@
-/*
- * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>
- * ****************************************************************************
- */
-package io.github.dsheirer.audio.playback;
-
-import io.github.dsheirer.audio.AudioFormats;
-import io.github.dsheirer.preference.UserPreferences;
-import io.github.dsheirer.source.mixer.MixerChannel;
-
-import javax.sound.sampled.Mixer;
-import java.nio.ByteBuffer;
-import java.nio.ByteOrder;
-import java.nio.ShortBuffer;
-
-/**
- * Mono Audio output implementation
- */
-public class MonoAudioOutput extends AudioOutput
-{
-    private final static int BUFFER_SIZE = 8000;
-
-    public MonoAudioOutput(Mixer mixer, UserPreferences userPreferences)
-    {
-        super(mixer, MixerChannel.MONO, AudioFormats.PCM_SIGNED_8000_HZ_16_BIT_MONO,
-            AudioFormats.MONO_SOURCE_DATALINE_INFO, BUFFER_SIZE, userPreferences);
-    }
-
-    /**
-     * Converts the audio packet data into mono audio frames.
-     */
-    protected ByteBuffer convert(float[] samples)
-    {
-        ByteBuffer buffer = null;
-
-        if(samples.length > 0)
-        {
-			/* Little-endian byte buffer */
-            buffer = ByteBuffer.allocate(samples.length * 2).order(ByteOrder.LITTLE_ENDIAN);
-
-            ShortBuffer shortBuffer = buffer.asShortBuffer();
-
-            for(float sample : samples)
-            {
-                shortBuffer.put((short) (sample * Short.MAX_VALUE));
-            }
-        }
-
-        return buffer;
-    }
-}

src/main/java/io/github/dsheirer/audio/playback/StereoAudioOutput.java

@@ -1,79 +0,0 @@
-/*
- * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>
- * ****************************************************************************
- */
-package io.github.dsheirer.audio.playback;
-
-import io.github.dsheirer.audio.AudioFormats;
-import io.github.dsheirer.preference.UserPreferences;
-import io.github.dsheirer.source.mixer.MixerChannel;
-
-import javax.sound.sampled.Mixer;
-import java.nio.ByteBuffer;
-import java.nio.ByteOrder;
-import java.nio.ShortBuffer;
-
-/**
- * Stereo audio output implementation.
- */
-public class StereoAudioOutput extends AudioOutput
-{
-    private final static int BUFFER_SIZE = 16000;
-
-    public StereoAudioOutput(Mixer mixer, MixerChannel channel, UserPreferences userPreferences)
-    {
-        super(mixer, channel, AudioFormats.PCM_SIGNED_8000_HZ_16BITS_STEREO, AudioFormats.STEREO_SOURCE_DATALINE_INFO,
-            BUFFER_SIZE, userPreferences);
-    }
-
-    /**
-     * Converts the audio packet data into stereo audio frames with the mixer
-     * channel containing the audio and the other channel containing zero
-     * valued (silent) samples.
-     */
-    protected ByteBuffer convert(float[] samples)
-    {
-        ByteBuffer buffer = null;
-
-        if(samples.length > 0)
-        {
-			/* Little-endian byte buffer */
-            buffer = ByteBuffer.allocate(samples.length * 4).order(ByteOrder.LITTLE_ENDIAN);
-
-            ShortBuffer shortBuffer = buffer.asShortBuffer();
-
-            if(getMixerChannel() == MixerChannel.LEFT)
-            {
-                for(float sample : samples)
-                {
-                    shortBuffer.put((short) (sample * Short.MAX_VALUE));
-                    shortBuffer.put((short) 0);
-                }
-            }
-            else
-            {
-                for(float sample : samples)
-                {
-                    shortBuffer.put((short) 0);
-                    shortBuffer.put((short) (sample * Short.MAX_VALUE));
-                }
-            }
-        }
-
-        return buffer;
-    }
-}

src/main/java/io/github/dsheirer/bits/BinaryMessage.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2025 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -306,6 +306,15 @@ public class BinaryMessage extends BitSet
     }
 
     public String toString()
+    {
+        return toHexString();
+    }
+
+    /**
+     * Binary representation of the message
+     * @return message in binary 0/1 format
+     */
+    public String toBinaryString()
     {
         StringBuilder sb = new StringBuilder();
 
@@ -317,6 +326,10 @@ public class BinaryMessage extends BitSet
         return sb.toString();
     }
 
+    /**
+     * Hex string representation of the message
+     * @return message in hex
+     */
     public String toHexString()
     {
         StringBuilder sb = new StringBuilder();
@@ -997,6 +1010,18 @@ public class BinaryMessage extends BitSet
         return String.format("%0" + width + "X", getInt(field));
     }
 
+    /**
+     * Returns the long field formatted as a hex value using zero prefixes to pad the hex character count to fully
+     * represent the size (width) of the field.
+     * @param field to parse as hex
+     * @return hex value.
+     */
+    public String getHex(LongField field)
+    {
+        int width = Math.ceilDiv(field.width(), 4);
+        return String.format("%0" + width + "X", getLong(field));
+    }
+
     /**
      * Format the byte value that starts at the specified index as hexadecimal.  If the length of the message is less
      * than the start index plus 7 bits, then the value represents those bits as high-order bits with zero padding in
@@ -1315,37 +1340,15 @@ public class BinaryMessage extends BitSet
             throw new IllegalArgumentException("Message must contain only 0-9 and A-F hexadecimal characters");
         }
 
-        int length = hex.length() / 2;
+        BinaryMessage message = new BinaryMessage(hex.length() * 4);
 
-        if(length * 2 < hex.length())
+        for(int x = 0; x < hex.length(); x++)
         {
-            length++;
+            String rawHex = hex.substring(x, x + 1);
+            message.setInt(Integer.parseInt(rawHex, 16), IntField.length4(x * 4));
         }
 
-        BinaryMessage buffer = new BinaryMessage(length * 8);
-
-        int bufferOffset = 0;
-        for(int x = 0; x < hex.length(); x += 2)
-        {
-            int endIndex = x + 2;
-            if(endIndex > hex.length())
-            {
-                endIndex--;
-            }
-
-            String rawHex = hex.substring(x, endIndex);
-
-            if(rawHex.length() == 1)
-            {
-                rawHex = rawHex + "0";
-            }
-
-            int value = Integer.parseInt(rawHex, 16);
-            buffer.setByte(bufferOffset, (byte)(value & 0xFF));
-            bufferOffset += 8;
-        }
-
-        return buffer;
+        return message;
     }
 
     /**

src/main/java/io/github/dsheirer/bits/CorrectedBinaryMessage.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2024 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -18,6 +18,7 @@
  */
 package io.github.dsheirer.bits;
 
+import java.nio.ByteOrder;
 import java.util.BitSet;
 
 public class CorrectedBinaryMessage extends BinaryMessage
@@ -54,6 +55,45 @@ public class CorrectedBinaryMessage extends BinaryMessage
         this.xor(message);
     }
 
+    /**
+     * Creates a new message loaded from the hexadecimal string
+     * @param hex representing the bits of the message
+     * @return new message
+     */
+    public static CorrectedBinaryMessage loadHex(String hex)
+    {
+        return new CorrectedBinaryMessage(BinaryMessage.loadHex(hex));
+    }
+
+    /**
+     * Overloads the parent method to return this type.
+     * @param binary message to load
+     * @return loaded message
+     */
+    public static CorrectedBinaryMessage load(String binary)
+    {
+        return new CorrectedBinaryMessage(BinaryMessage.load(binary));
+    }
+
+    /**
+     * Constructs a binary frame from the byte array with length set to the
+     * number of bits contained in the byte array
+     */
+    public static CorrectedBinaryMessage from(byte[] data, ByteOrder byteOrder)
+    {
+        if(byteOrder == ByteOrder.LITTLE_ENDIAN)
+        {
+            return new CorrectedBinaryMessage(from(data));
+        }
+        else
+        {
+            CorrectedBinaryMessage frame = new CorrectedBinaryMessage(data.length * 8);
+            BitSet bitSet = BitSet.valueOf(data);
+            frame.xor(bitSet);
+            return frame;
+        }
+    }
+
     @Override
     public int getCorrectedBitCount()
     {

src/main/java/io/github/dsheirer/bits/IntField.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2025 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -60,7 +60,27 @@ public record IntField(int start, int end)
     }
 
     /**
-     * Utility constructor method for a field with one four bits of length.
+     * Utility constructor method for a field with two bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static IntField length2(int start)
+    {
+        return new IntField(start, (start + 1));
+    }
+
+    /**
+     * Utility constructor method for a field with three bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static IntField length3(int start)
+    {
+        return new IntField(start, (start + 2));
+    }
+
+    /**
+     * Utility constructor method for a field with four bits of length.
      * @param start index (inclusive)
      * @return constructed bit field.
      */
@@ -70,7 +90,17 @@ public record IntField(int start, int end)
     }
 
     /**
-     * Utility constructor method for a field with one four bits of length.
+     * Utility constructor method for a field with five bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static IntField length5(int start)
+    {
+        return new IntField(start, (start + 4));
+    }
+
+    /**
+     * Utility constructor method for a field with six bits of length.
      * @param start index (inclusive)
      * @return constructed bit field.
      */
@@ -79,6 +109,16 @@ public record IntField(int start, int end)
         return new IntField(start, (start + 5));
     }
 
+    /**
+     * Utility constructor method for a field with seven bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static IntField length7(int start)
+    {
+        return new IntField(start, (start + 6));
+    }
+
     /**
      * Utility constructor method for a field with one octet of length.
      * @param start index (inclusive)
@@ -89,6 +129,36 @@ public record IntField(int start, int end)
         return new IntField(start, (start + 7));
     }
 
+    /**
+     * Utility constructor method for a field with nine bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static IntField length9(int start)
+    {
+        return new IntField(start, (start + 8));
+    }
+
+    /**
+     * Utility constructor method for a field with ten bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static IntField length10(int start)
+    {
+        return new IntField(start, (start + 9));
+    }
+
+    /**
+     * Utility constructor method for a field with eleven bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static IntField length11(int start)
+    {
+        return new IntField(start, (start + 10));
+    }
+
     /**
      * Utility constructor method for a field with 12 bits of length.
      * @param start index (inclusive)
@@ -99,6 +169,26 @@ public record IntField(int start, int end)
         return new IntField(start, (start + 11));
     }
 
+    /**
+     * Utility constructor method for a field with 14 bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static IntField length14(int start)
+    {
+        return new IntField(start, (start + 13));
+    }
+
+    /**
+     * Utility constructor method for a field with 15 bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static IntField length15(int start)
+    {
+        return new IntField(start, (start + 14));
+    }
+
     /**
      * Utility constructor method for a field with two octets of length.
      * @param start index (inclusive)

src/main/java/io/github/dsheirer/bits/LongField.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2024 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -39,6 +39,15 @@ public record LongField(int start, int end)
         }
     }
 
+    /**
+     * Width of the field in bit positions
+     * @return width
+     */
+    public int width()
+    {
+        return end() - start() + 1;
+    }
+
     /**
      * Utility constructor method.
      * @param start index (inclusive)
@@ -101,7 +110,17 @@ public record LongField(int start, int end)
     }
 
     /**
-     * Utility constructor method for a field with two octets of length.
+     * Utility constructor method for a field with 23 bits of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static LongField length23(int start)
+    {
+        return new LongField(start, (start + 22));
+    }
+
+    /**
+     * Utility constructor method for a field with three octets of length.
      * @param start index (inclusive)
      * @return constructed bit field.
      */
@@ -111,7 +130,7 @@ public record LongField(int start, int end)
     }
 
     /**
-     * Utility constructor method for a field with three octets of length.
+     * Utility constructor method for a field with four octets of length.
      * @param start index (inclusive)
      * @return constructed bit field.
      */
@@ -119,4 +138,24 @@ public record LongField(int start, int end)
     {
         return new LongField(start, (start + 31));
     }
+
+    /**
+     * Utility constructor method for a field with seven octets of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static LongField length56(int start)
+    {
+        return new LongField(start, (start + 55));
+    }
+
+    /**
+     * Utility constructor method for a field with eight octets of length.
+     * @param start index (inclusive)
+     * @return constructed bit field.
+     */
+    public static LongField length64(int start)
+    {
+        return new LongField(start, (start + 63));
+    }
 }

src/main/java/io/github/dsheirer/buffer/FloatCircularBuffer.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2023 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -98,6 +98,33 @@ public class FloatCircularBuffer
         return values;
     }
 
+    /**
+     * Gets all sample values in reverse order.
+     */
+    public float[] getAllReversed()
+    {
+        int valuePointer = 0;
+        float[] values = new float[mBuffer.length];
+        int bufferPointer = mBufferPointer - 1;
+
+        if(bufferPointer < 0)
+        {
+            bufferPointer = mBuffer.length - 1;
+        }
+
+        while(valuePointer < values.length)
+        {
+            values[valuePointer++] = mBuffer[bufferPointer--];
+
+            if(bufferPointer < 0)
+            {
+                bufferPointer = mBuffer.length - 1;
+            }
+        }
+
+        return values;
+    }
+
     /**
      * Places the new value into the buffer, overwriting the oldest value
      * @param newValue to add to the buffer

src/main/java/io/github/dsheirer/buffer/FloatNativeBuffer.java

@@ -100,8 +100,10 @@ public class FloatNativeBuffer extends AbstractNativeBuffer
                 throw new IllegalStateException("No more samples");
             }
 
-            float[] chunk = Arrays.copyOfRange(mInterleavedComplexSamples, mBufferPointer, mBufferPointer + BUFFER_SIZE * 2);
-            mBufferPointer += BUFFER_SIZE * 2;
+            //The final chunk holds the remaining samples, so that it isn't padded with zero valued samples
+            int end = Math.min(mBufferPointer + BUFFER_SIZE * 2, mInterleavedComplexSamples.length);
+            float[] chunk = Arrays.copyOfRange(mInterleavedComplexSamples, mBufferPointer, end);
+            mBufferPointer = end;
 
             return SampleUtils.deinterleave(chunk, getTimestamp());
         }
@@ -125,8 +127,10 @@ public class FloatNativeBuffer extends AbstractNativeBuffer
                 throw new IllegalStateException("No more samples");
             }
 
-            float[] chunk = Arrays.copyOfRange(mInterleavedComplexSamples, mBufferPointer, mBufferPointer + BUFFER_SIZE * 2);
-            mBufferPointer += BUFFER_SIZE * 2;
+            //The final chunk holds the remaining samples, so that it isn't padded with zero valued samples
+            int end = Math.min(mBufferPointer + BUFFER_SIZE * 2, mInterleavedComplexSamples.length);
+            float[] chunk = Arrays.copyOfRange(mInterleavedComplexSamples, mBufferPointer, end);
+            mBufferPointer = end;
 
             return new InterleavedComplexSamples(chunk, getTimestamp());
         }

src/main/java/io/github/dsheirer/buffer/NativeSampleDelayBuffer.java

@@ -116,7 +116,8 @@ public class NativeSampleDelayBuffer implements Listener<INativeBuffer>
             actionRequest = mActionQueue.poll();
         }
 
-        mBroadcaster.receive(samples);
+        //The delay queue stores the unconverted buffer since it's more compact than the converted samples
+        mBroadcaster.receive(mBroadcaster.getListenerCount() > 1 ? new SharedNativeBuffer(samples) : samples);
 
         //Store the new buffer in the delay queue and increment the pointer
         mDelayBuffer[mDelayBufferPointer++] = samples;

src/main/java/io/github/dsheirer/buffer/SharedNativeBuffer.java

@@ -0,0 +1,114 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2023 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+package io.github.dsheirer.buffer;
+
+import io.github.dsheirer.sample.complex.ComplexSamples;
+import io.github.dsheirer.sample.complex.InterleavedComplexSamples;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.NoSuchElementException;
+
+/**
+ * Native buffer wrapper that lets multiple channels share one conversion of the native samples.  Each channel's
+ * iterator returns the same complex samples instances, on the channel's own thread, so consumers must not modify the
+ * samples.  The converted samples are released when the channels release this wrapper.
+ */
+public class SharedNativeBuffer implements INativeBuffer
+{
+    private final INativeBuffer mNativeBuffer;
+    private final List<ComplexSamples> mConverted = new ArrayList<>();
+    private Iterator<ComplexSamples> mConverter;
+
+    /**
+     * Constructs an instance
+     * @param nativeBuffer to convert
+     */
+    public SharedNativeBuffer(INativeBuffer nativeBuffer)
+    {
+        mNativeBuffer = nativeBuffer;
+    }
+
+    /**
+     * Indicates if the converted samples include the index, converting the next samples as needed.
+     */
+    private synchronized boolean hasConverted(int index)
+    {
+        if(mConverter == null)
+        {
+            mConverter = mNativeBuffer.iterator();
+        }
+
+        if(index == mConverted.size() && mConverter.hasNext())
+        {
+            mConverted.add(mConverter.next());
+        }
+
+        return index < mConverted.size();
+    }
+
+    private synchronized ComplexSamples getConverted(int index)
+    {
+        return mConverted.get(index);
+    }
+
+    @Override
+    public Iterator<ComplexSamples> iterator()
+    {
+        return new Iterator<>()
+        {
+            private int mIndex = 0;
+
+            @Override
+            public boolean hasNext()
+            {
+                return hasConverted(mIndex);
+            }
+
+            @Override
+            public ComplexSamples next()
+            {
+                if(!hasNext())
+                {
+                    throw new NoSuchElementException("No more samples");
+                }
+
+                return getConverted(mIndex++);
+            }
+        };
+    }
+
+    @Override
+    public Iterator<InterleavedComplexSamples> iteratorInterleaved()
+    {
+        return mNativeBuffer.iteratorInterleaved();
+    }
+
+    @Override
+    public int sampleCount()
+    {
+        return mNativeBuffer.sampleCount();
+    }
+
+    @Override
+    public long getTimestamp()
+    {
+        return mNativeBuffer.getTimestamp();
+    }
+}

src/main/java/io/github/dsheirer/buffer/airspy/AirspyHfNativeBuffer.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2023 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy.hf;
+package io.github.dsheirer.buffer.airspy;
 
 import io.github.dsheirer.buffer.AbstractNativeBuffer;
 import io.github.dsheirer.sample.complex.ComplexSamples;

src/main/java/io/github/dsheirer/buffer/airspy/AirspyHfNativeBufferFactory.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2023 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy.hf;
+package io.github.dsheirer.buffer.airspy;
 
 import io.github.dsheirer.buffer.AbstractNativeBufferFactory;
 import io.github.dsheirer.buffer.DcCorrectionManager;

src/main/java/io/github/dsheirer/buffer/sample/ISampleConverter.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,18 +17,18 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import java.nio.ByteBuffer;
 
 /**
- * Interface to convert airspy samples from a byte buffer to an array of shorts.
+ * Interface to convert samples from a byte buffer to an array of shorts.
  */
-public interface IAirspySampleConverter
+public interface ISampleConverter
 {
     /**
-     * Converts the airspy byte samples contained in the byte buffer to their short-valued representation
-     * @param buffer of airspy samples
+     * Converts the byte samples contained in the byte buffer to their short-valued representation
+     * @param buffer of samples
      * @return converted samples
      */
     short[] convert(ByteBuffer buffer);

src/main/java/io/github/dsheirer/buffer/sample/SampleBufferIterator.java

@@ -17,17 +17,17 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.dsp.filter.hilbert.HilbertTransform;
 import java.util.Iterator;
 
 /**
- * Base complex samples iterator for raw Airspy sample buffers.  Incorporates a Hilbert transform filter
+ * Base complex samples iterator for raw sample buffers.  Incorporates a Hilbert transform filter
  * for converting the real sample array to complex samples.
  * @param <T> either ComplexSamples or InterleavedComplexSamples
  */
-public abstract class AirspyBufferIterator<T> implements Iterator<T>
+public abstract class SampleBufferIterator<T> implements Iterator<T>
 {
     protected static final float SCALE_SIGNED_12_BIT_TO_FLOAT = 1.0f / 2048.0f;
     protected static final int FRAGMENT_SIZE = 4096;
@@ -47,14 +47,14 @@ public abstract class AirspyBufferIterator<T> implements Iterator<T>
 
     /**
      * Constructs an instance
-     * @param samples from the airspy.
+     * @param samples from the tuner.
      * @param residualI samples from previous buffer
      * @param residualQ samples from previous buffer
      * @param averageDc as measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyBufferIterator(short[] samples, short[] residualI, short[] residualQ, float averageDc, long timestamp,
+    public SampleBufferIterator(short[] samples, short[] residualI, short[] residualQ, float averageDc, long timestamp,
                                 float samplesPerMillisecond)
     {
         if(residualI.length != I_OVERLAP || residualQ.length != Q_OVERLAP)

src/main/java/io/github/dsheirer/buffer/sample/SampleBufferIteratorScalar.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,27 +17,27 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.ComplexSamples;
 import java.util.Arrays;
 
 /**
- * Scalar implementation for non-packed Airspy native buffers
+ * Scalar implementation for non-packed native buffers
  */
-public class AirspyBufferIteratorScalar extends AirspyBufferIterator<ComplexSamples>
+public class SampleBufferIteratorScalar extends SampleBufferIterator<ComplexSamples>
 {
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyBufferIteratorScalar(short[] samples, short[] residualI, short[] residualQ, float averageDc, long timestamp, float samplesPerMillisecond)
+    public SampleBufferIteratorScalar(short[] samples, short[] residualI, short[] residualQ, float averageDc, long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);
     }

src/main/java/io/github/dsheirer/buffer/sample/SampleBufferIteratorVector128Bits.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.ComplexSamples;
 import java.util.Arrays;
@@ -26,23 +26,23 @@ import jdk.incubator.vector.VectorOperators;
 import jdk.incubator.vector.VectorSpecies;
 
 /**
- * Vector SIMD implementation for non-packed Airspy native buffers
+ * Vector SIMD implementation for non-packed native buffers
  */
-public class AirspyBufferIteratorVector128Bits extends AirspyBufferIterator<ComplexSamples>
+public class SampleBufferIteratorVector128Bits extends SampleBufferIterator<ComplexSamples>
 {
     private static final VectorSpecies<Float> VECTOR_SPECIES = FloatVector.SPECIES_128;
 
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyBufferIteratorVector128Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleBufferIteratorVector128Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                                              long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);

src/main/java/io/github/dsheirer/buffer/sample/SampleBufferIteratorVector256Bits.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.ComplexSamples;
 import java.util.Arrays;
@@ -26,23 +26,23 @@ import jdk.incubator.vector.VectorOperators;
 import jdk.incubator.vector.VectorSpecies;
 
 /**
- * Vector SIMD implementation for non-packed Airspy native buffers
+ * Vector SIMD implementation for non-packed native buffers
  */
-public class AirspyBufferIteratorVector256Bits extends AirspyBufferIterator<ComplexSamples>
+public class SampleBufferIteratorVector256Bits extends SampleBufferIterator<ComplexSamples>
 {
     private static final VectorSpecies<Float> VECTOR_SPECIES = FloatVector.SPECIES_256;
 
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyBufferIteratorVector256Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleBufferIteratorVector256Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                                              long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);

src/main/java/io/github/dsheirer/buffer/sample/SampleBufferIteratorVector512Bits.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.ComplexSamples;
 import java.util.Arrays;
@@ -26,9 +26,9 @@ import jdk.incubator.vector.VectorOperators;
 import jdk.incubator.vector.VectorSpecies;
 
 /**
- * Vector SIMD implementation for non-packed Airspy native buffers
+ * Vector SIMD implementation for non-packed native buffers
  */
-public class AirspyBufferIteratorVector512Bits extends AirspyBufferIterator<ComplexSamples>
+public class SampleBufferIteratorVector512Bits extends SampleBufferIterator<ComplexSamples>
 {
     private static final VectorSpecies<Float> VECTOR_SPECIES = FloatVector.SPECIES_512;
     private float[] mFilterPart2;
@@ -36,14 +36,14 @@ public class AirspyBufferIteratorVector512Bits extends AirspyBufferIterator<Comp
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyBufferIteratorVector512Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleBufferIteratorVector512Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                                              long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);

src/main/java/io/github/dsheirer/buffer/sample/SampleBufferIteratorVector64Bits.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.ComplexSamples;
 import java.util.Arrays;
@@ -26,23 +26,23 @@ import jdk.incubator.vector.VectorOperators;
 import jdk.incubator.vector.VectorSpecies;
 
 /**
- * Vector SIMD implementation for non-packed Airspy native buffers
+ * Vector SIMD implementation for non-packed native buffers
  */
-public class AirspyBufferIteratorVector64Bits extends AirspyBufferIterator<ComplexSamples>
+public class SampleBufferIteratorVector64Bits extends SampleBufferIterator<ComplexSamples>
 {
     private static final VectorSpecies<Float> VECTOR_SPECIES = FloatVector.SPECIES_64;
 
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyBufferIteratorVector64Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleBufferIteratorVector64Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                                             long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);

src/main/java/io/github/dsheirer/buffer/sample/SampleInterleavedBufferIteratorScalar.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,26 +17,26 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.InterleavedComplexSamples;
 
 /**
- * Scalar implementation for non-packed Airspy native buffers
+ * Scalar implementation for non-packed native buffers
  */
-public class AirspyInterleavedBufferIteratorScalar extends AirspyBufferIterator<InterleavedComplexSamples>
+public class SampleInterleavedBufferIteratorScalar extends SampleBufferIterator<InterleavedComplexSamples>
 {
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyInterleavedBufferIteratorScalar(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleInterleavedBufferIteratorScalar(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                                                  long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);

src/main/java/io/github/dsheirer/buffer/sample/SampleInterleavedBufferIteratorVector128Bits.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.InterleavedComplexSamples;
 import jdk.incubator.vector.FloatVector;
@@ -25,23 +25,23 @@ import jdk.incubator.vector.VectorOperators;
 import jdk.incubator.vector.VectorSpecies;
 
 /**
- * Vector SIMD implementation for non-packed Airspy native buffers
+ * Vector SIMD implementation for non-packed native buffers
  */
-public class AirspyInterleavedBufferIteratorVector128Bits extends AirspyBufferIterator<InterleavedComplexSamples>
+public class SampleInterleavedBufferIteratorVector128Bits extends SampleBufferIterator<InterleavedComplexSamples>
 {
     private static final VectorSpecies<Float> VECTOR_SPECIES = FloatVector.SPECIES_128;
 
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyInterleavedBufferIteratorVector128Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleInterleavedBufferIteratorVector128Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                                                         long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);

src/main/java/io/github/dsheirer/buffer/sample/SampleInterleavedBufferIteratorVector256Bits.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.InterleavedComplexSamples;
 import jdk.incubator.vector.FloatVector;
@@ -25,23 +25,23 @@ import jdk.incubator.vector.VectorOperators;
 import jdk.incubator.vector.VectorSpecies;
 
 /**
- * Vector SIMD implementation for non-packed Airspy native buffers
+ * Vector SIMD implementation for non-packed native buffers
  */
-public class AirspyInterleavedBufferIteratorVector256Bits extends AirspyBufferIterator<InterleavedComplexSamples>
+public class SampleInterleavedBufferIteratorVector256Bits extends SampleBufferIterator<InterleavedComplexSamples>
 {
     private static final VectorSpecies<Float> VECTOR_SPECIES = FloatVector.SPECIES_256;
 
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyInterleavedBufferIteratorVector256Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleInterleavedBufferIteratorVector256Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                                                         long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);

src/main/java/io/github/dsheirer/buffer/sample/SampleInterleavedBufferIteratorVector512Bits.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.InterleavedComplexSamples;
 import jdk.incubator.vector.FloatVector;
@@ -25,9 +25,9 @@ import jdk.incubator.vector.VectorOperators;
 import jdk.incubator.vector.VectorSpecies;
 
 /**
- * Vector SIMD implementation for non-packed Airspy native buffers
+ * Vector SIMD implementation for non-packed native buffers
  */
-public class AirspyInterleavedBufferIteratorVector512Bits extends AirspyBufferIterator<InterleavedComplexSamples>
+public class SampleInterleavedBufferIteratorVector512Bits extends SampleBufferIterator<InterleavedComplexSamples>
 {
     private static final VectorSpecies<Float> VECTOR_SPECIES = FloatVector.SPECIES_512;
     private float[] mFilterPart2;
@@ -35,14 +35,14 @@ public class AirspyInterleavedBufferIteratorVector512Bits extends AirspyBufferIt
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyInterleavedBufferIteratorVector512Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleInterleavedBufferIteratorVector512Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                                                         long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);

src/main/java/io/github/dsheirer/buffer/sample/SampleInterleavedBufferIteratorVector64Bits.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.sample.complex.InterleavedComplexSamples;
 import jdk.incubator.vector.FloatVector;
@@ -25,23 +25,23 @@ import jdk.incubator.vector.VectorOperators;
 import jdk.incubator.vector.VectorSpecies;
 
 /**
- * Vector SIMD implementation for non-packed Airspy native buffers
+ * Vector SIMD implementation for non-packed native buffers
  */
-public class AirspyInterleavedBufferIteratorVector64Bits extends AirspyBufferIterator<InterleavedComplexSamples>
+public class SampleInterleavedBufferIteratorVector64Bits extends SampleBufferIterator<InterleavedComplexSamples>
 {
     private static final VectorSpecies<Float> VECTOR_SPECIES = FloatVector.SPECIES_64;
 
     /**
      * Constructs an instance
      *
-     * @param samples from the airspy, either packed or unpacked.
+     * @param samples from the device, either packed or unpacked.
      * @param residualI samples from last buffer
      * @param residualQ samples from last buffer
      * @param averageDc measured
      * @param timestamp of the buffer
      * @param samplesPerMillisecond to calculate sub-buffer fragment timestamps
      */
-    public AirspyInterleavedBufferIteratorVector64Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleInterleavedBufferIteratorVector64Bits(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                                                        long timestamp, float samplesPerMillisecond)
     {
         super(samples, residualI, residualQ, averageDc, timestamp, samplesPerMillisecond);

src/main/java/io/github/dsheirer/buffer/sample/SampleNativeBuffer.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.buffer.AbstractNativeBuffer;
 import io.github.dsheirer.sample.complex.ComplexSamples;
@@ -26,20 +26,20 @@ import io.github.dsheirer.vector.calibrate.Implementation;
 import java.util.Iterator;
 
 /**
- * Native buffer scalar implementation for Airspy non-packed samples.
+ * Native buffer scalar implementation for non-packed samples.
  */
-public class AirspyNativeBuffer extends AbstractNativeBuffer
+public class SampleNativeBuffer extends AbstractNativeBuffer
 {
-    private short[] mSamples;
-    private short[] mResidualI;
-    private short[] mResidualQ;
-    private float mAverageDc;
-    private Implementation mInterleavedImplementation;
-    private Implementation mNonInterleavedImplementation;
+    private final short[] mSamples;
+    private final short[] mResidualI;
+    private final short[] mResidualQ;
+    private final float mAverageDc;
+    private final Implementation mInterleavedImplementation;
+    private final Implementation mNonInterleavedImplementation;
 
     /**
      * Constructs an instance
-     * @param samples (non-packed) from the airspy device
+     * @param samples (non-packed) from the device
      * @param residualI samples from previous buffer
      * @param residualQ samples from previous buffer
      * @param averageDc measured
@@ -48,17 +48,17 @@ public class AirspyNativeBuffer extends AbstractNativeBuffer
      * @param nonInterleavedImplementation optimal, scalar vs vector SIMD
      * @param samplesPerMillisecond used to calculate sub-buffer fragment timestamp offsets from the start of this buffer.
      */
-    public AirspyNativeBuffer(short[] samples, short[] residualI, short[] residualQ, float averageDc,
+    public SampleNativeBuffer(short[] samples, short[] residualI, short[] residualQ, float averageDc,
                               long timestamp, Implementation interleavedImplementation,
                               Implementation nonInterleavedImplementation, float samplesPerMillisecond)
     {
         super(timestamp, samplesPerMillisecond);
 
         //Ensure we're an even multiple of the fragment size.  Typically, this will be 64k or 128k
-        if(samples.length % AirspyBufferIterator.FRAGMENT_SIZE != 0)
+        if(samples.length % SampleBufferIterator.FRAGMENT_SIZE != 0)
         {
             throw new IllegalArgumentException("Samples short[] length [" + samples.length +
-                    "] must be an even multiple of " + AirspyBufferIterator.FRAGMENT_SIZE);
+                    "] must be an even multiple of " + SampleBufferIterator.FRAGMENT_SIZE);
         }
 
         mSamples = samples;
@@ -78,13 +78,13 @@ public class AirspyNativeBuffer extends AbstractNativeBuffer
     @Override
     public Iterator<ComplexSamples> iterator()
     {
-        return switch(mInterleavedImplementation)
+        return switch(mNonInterleavedImplementation)
         {
-            case VECTOR_SIMD_512 -> new AirspyBufferIteratorVector512Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
-            case VECTOR_SIMD_256-> new AirspyBufferIteratorVector256Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
-            case VECTOR_SIMD_128-> new AirspyBufferIteratorVector128Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
-            case VECTOR_SIMD_64 ->new AirspyBufferIteratorVector64Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
-            default -> new AirspyBufferIteratorScalar(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            case VECTOR_SIMD_512 -> new SampleBufferIteratorVector512Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            case VECTOR_SIMD_256-> new SampleBufferIteratorVector256Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            case VECTOR_SIMD_128-> new SampleBufferIteratorVector128Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            case VECTOR_SIMD_64 ->new SampleBufferIteratorVector64Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            default -> new SampleBufferIteratorScalar(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
         };
     }
 
@@ -93,11 +93,11 @@ public class AirspyNativeBuffer extends AbstractNativeBuffer
     {
         return switch(mInterleavedImplementation)
         {
-            case VECTOR_SIMD_512 -> new AirspyInterleavedBufferIteratorVector512Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
-            case VECTOR_SIMD_256-> new AirspyInterleavedBufferIteratorVector256Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
-            case VECTOR_SIMD_128-> new AirspyInterleavedBufferIteratorVector128Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
-            case VECTOR_SIMD_64 ->new AirspyInterleavedBufferIteratorVector64Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
-            default -> new AirspyInterleavedBufferIteratorScalar(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            case VECTOR_SIMD_512 -> new SampleInterleavedBufferIteratorVector512Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            case VECTOR_SIMD_256-> new SampleInterleavedBufferIteratorVector256Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            case VECTOR_SIMD_128-> new SampleInterleavedBufferIteratorVector128Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            case VECTOR_SIMD_64 ->new SampleInterleavedBufferIteratorVector64Bits(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
+            default -> new SampleInterleavedBufferIteratorScalar(mSamples, mResidualI, mResidualQ, mAverageDc, getTimestamp(), getSamplesPerMillisecond());
         };
     }
 }

src/main/java/io/github/dsheirer/buffer/sample/SampleNativeBufferFactory.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.buffer.AbstractNativeBufferFactory;
 import io.github.dsheirer.buffer.INativeBuffer;
@@ -30,26 +30,26 @@ import java.util.Arrays;
 /**
  * Implements a factory for creating SignedByteNativeBuffer instances
  */
-public class AirspyNativeBufferFactory extends AbstractNativeBufferFactory
+public class SampleNativeBufferFactory extends AbstractNativeBufferFactory
 {
     private boolean mSamplePacking = false;
-    private short[] mResidualI = new short[AirspyBufferIterator.I_OVERLAP];
-    private short[] mResidualQ = new short[AirspyBufferIterator.Q_OVERLAP];
-    private IAirspySampleConverter mConverter;
+    private short[] mResidualI = new short[SampleBufferIterator.I_OVERLAP];
+    private short[] mResidualQ = new short[SampleBufferIterator.Q_OVERLAP];
+    private ISampleConverter mConverter;
     private Implementation mInterleavedIteratorImplementation;
     private Implementation mNonInterleavedIteratorImplementation;
 
     /**
      * Constructs an instance
      */
-    public AirspyNativeBufferFactory()
+    public SampleNativeBufferFactory()
     {
         updateConverter();
 
         mInterleavedIteratorImplementation = CalibrationManager.getInstance()
-                .getImplementation(CalibrationType.AIRSPY_UNPACKED_INTERLEAVED_ITERATOR);
+                .getImplementation(CalibrationType.SAMPLE_UNPACKED_INTERLEAVED_ITERATOR);
         mNonInterleavedIteratorImplementation = CalibrationManager.getInstance()
-                .getImplementation(CalibrationType.AIRSPY_UNPACKED_ITERATOR);
+                .getImplementation(CalibrationType.SAMPLE_UNPACKED_ITERATOR);
     }
 
     /**
@@ -78,7 +78,7 @@ public class AirspyNativeBufferFactory extends AbstractNativeBufferFactory
         }
         else
         {
-            Implementation implementation = CalibrationManager.getInstance().getImplementation(CalibrationType.AIRSPY_SAMPLE_CONVERTER);
+            Implementation implementation = CalibrationManager.getInstance().getImplementation(CalibrationType.SAMPLE_PACKED_CONVERTER);
 
             if(implementation == Implementation.VECTOR_SIMD_PREFERRED)
             {
@@ -102,7 +102,7 @@ public class AirspyNativeBufferFactory extends AbstractNativeBufferFactory
     {
         short[] samples = mConverter.convert(buffer);
 
-        INativeBuffer nativeBuffer = new AirspyNativeBuffer(samples,
+        INativeBuffer nativeBuffer = new SampleNativeBuffer(samples,
                 Arrays.copyOf(mResidualI, mResidualI.length),
                 Arrays.copyOf(mResidualQ, mResidualQ.length), mConverter.getAverageDc(), timestamp,
                 mInterleavedIteratorImplementation, mNonInterleavedIteratorImplementation, getSamplesPerMillisecond());
@@ -118,16 +118,16 @@ public class AirspyNativeBufferFactory extends AbstractNativeBufferFactory
      */
     private void extractResidual(short[] samples)
     {
-        int offset = samples.length - (AirspyBufferIterator.I_OVERLAP * 2);
+        int offset = samples.length - (SampleBufferIterator.I_OVERLAP * 2);
 
-        for(int i = 0; i < AirspyBufferIterator.I_OVERLAP; i++)
+        for(int i = 0; i < SampleBufferIterator.I_OVERLAP; i++)
         {
             mResidualI[i] = samples[offset + (2 * i)];
         }
 
-        offset = samples.length - (AirspyBufferIterator.Q_OVERLAP * 2) + 1;
+        offset = samples.length - (SampleBufferIterator.Q_OVERLAP * 2) + 1;
 
-        for(int q = 0; q < AirspyBufferIterator.Q_OVERLAP; q++)
+        for(int q = 0; q < SampleBufferIterator.Q_OVERLAP; q++)
         {
             mResidualQ[q] = samples[offset + (2 * q)];
         }

src/main/java/io/github/dsheirer/buffer/sample/ScalarPackedSampleConverter.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,15 +17,15 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.buffer.DcCorrectionManager;
 import java.nio.ByteBuffer;
 
 /**
- * Scalar implementation of airspy sample converter for un-packed samples.
+ * Scalar implementation of sample converter for un-packed samples.
  */
-public class ScalarPackedSampleConverter implements IAirspySampleConverter
+public class ScalarPackedSampleConverter implements ISampleConverter
 {
     /**
      * Manages DC calculations and processing interval
@@ -64,7 +64,7 @@ public class ScalarPackedSampleConverter implements IAirspySampleConverter
             }
 
             float averageDcNow = ((float)dcAccumulator / (float)samples.length) - 2048.0f;
-            averageDcNow *= AirspyBufferIterator.SCALE_SIGNED_12_BIT_TO_FLOAT;
+            averageDcNow *= SampleBufferIterator.SCALE_SIGNED_12_BIT_TO_FLOAT;
             mDcCalculationManager.adjust(averageDcNow);
         }
         else

src/main/java/io/github/dsheirer/buffer/sample/ScalarUnpackedSampleConverter.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,15 +17,15 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.buffer.DcCorrectionManager;
 import java.nio.ByteBuffer;
 
 /**
- * Scalar implementation of airspy sample converter for un-packed samples.
+ * Scalar implementation of sample converter for un-packed samples.
  */
-public class ScalarUnpackedSampleConverter implements IAirspySampleConverter
+public class ScalarUnpackedSampleConverter implements ISampleConverter
 {
     /**
      * Manages DC calculations and processing interval
@@ -58,7 +58,7 @@ public class ScalarUnpackedSampleConverter implements IAirspySampleConverter
             }
 
             float averageDcNow = ((float)dcAccumulator / (float)samples.length) - 2048.0f;
-            averageDcNow *= AirspyBufferIterator.SCALE_SIGNED_12_BIT_TO_FLOAT;
+            averageDcNow *= SampleBufferIterator.SCALE_SIGNED_12_BIT_TO_FLOAT;
             mDcCalculationManager.adjust(averageDcNow);
         }
         else

src/main/java/io/github/dsheirer/buffer/sample/VectorUnpackedSampleConverter.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2022 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
  * ****************************************************************************
  */
 
-package io.github.dsheirer.buffer.airspy;
+package io.github.dsheirer.buffer.sample;
 
 import io.github.dsheirer.buffer.DcCorrectionManager;
 import java.nio.ByteBuffer;
@@ -26,9 +26,9 @@ import jdk.incubator.vector.VectorOperators;
 import jdk.incubator.vector.VectorSpecies;
 
 /**
- * Scalar implementation of airspy sample converter for un-packed samples.
+ * Scalar implementation of sample converter for un-packed samples.
  */
-public class VectorUnpackedSampleConverter implements IAirspySampleConverter
+public class VectorUnpackedSampleConverter implements ISampleConverter
 {
     private static final VectorSpecies<Short> VECTOR_SPECIES = ShortVector.SPECIES_PREFERRED;
 
@@ -88,7 +88,7 @@ public class VectorUnpackedSampleConverter implements IAirspySampleConverter
             }
 
             float averageDcNow = ((float)dcAccumulator / (float)samples.length) - 2048.0f;
-            averageDcNow *= AirspyBufferIterator.SCALE_SIGNED_12_BIT_TO_FLOAT;
+            averageDcNow *= SampleBufferIterator.SCALE_SIGNED_12_BIT_TO_FLOAT;
             mDcCalculationManager.adjust(averageDcNow);
         }
         else

src/main/java/io/github/dsheirer/channel/IBandChannelDescriptor.java

@@ -0,0 +1,40 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2025 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+package io.github.dsheirer.channel;
+
+import io.github.dsheirer.module.decode.p25.phase1.message.IFrequencyBand;
+
+/**
+ * Frequency band channel descriptor
+ */
+public interface IBandChannelDescriptor extends IChannelDescriptor
+{
+
+    /**
+     * Frequency band identifiers (0 - 15)
+     */
+    int[] getFrequencyBandIdentifiers();
+
+    /**
+     * Assigns the frequency band message to the channel to use in calculating the up/downlink frequencies
+     * @param bandIdentifier
+     */
+    void setFrequencyBand(IFrequencyBand bandIdentifier);
+
+}

src/main/java/io/github/dsheirer/channel/IChannelDescriptor.java

@@ -1,7 +1,6 @@
 /*
- * ******************************************************************************
- * sdrtrunk
- * Copyright (C) 2014-2019 Dennis Sheirer
+ * *****************************************************************************
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -15,41 +14,29 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>
- * *****************************************************************************
+ * ****************************************************************************
  */
+
 package io.github.dsheirer.channel;
 
-import io.github.dsheirer.module.decode.p25.phase1.message.IFrequencyBand;
 import io.github.dsheirer.protocol.Protocol;
 
-/**
- * Channel descriptor
- */
 public interface IChannelDescriptor
 {
     /**
      * Downlink frequency for the channel
+     *
      * @return frequency in hertz
      */
     long getDownlinkFrequency();
 
     /**
      * Uplink frequency for the channel
+     *
      * @return frequency in hertz
      */
     long getUplinkFrequency();
 
-    /**
-     * Frequency band identifiers (0 - 15)
-     */
-    int[] getFrequencyBandIdentifiers();
-
-    /**
-     * Assigns the frequency band message to the channel to use in calculating the up/downlink frequencies
-     * @param bandIdentifier
-     */
-    void setFrequencyBand(IFrequencyBand bandIdentifier);
-
     /**
      * Indicates if the timeslot count is greater than 1;
      */

src/main/java/io/github/dsheirer/channel/metadata/ChannelMetadataPanel.java

@@ -27,6 +27,7 @@ import io.github.dsheirer.controller.channel.ChannelModel;
 import io.github.dsheirer.controller.channel.ChannelProcessingManager;
 import io.github.dsheirer.eventbus.MyEventBus;
 import io.github.dsheirer.gui.playlist.channel.ViewChannelRequest;
+import io.github.dsheirer.gui.theme.ThemeManager;
 import io.github.dsheirer.icon.IconModel;
 import io.github.dsheirer.identifier.Identifier;
 import io.github.dsheirer.identifier.configuration.FrequencyConfigurationIdentifier;
@@ -246,7 +247,8 @@ public class ChannelMetadataPanel extends JPanel implements ListSelectionListene
                 {
                     label.setText(Joiner.on(", ").skipNulls().join(aliases));
                     label.setIcon(mIconModel.getIcon(aliases.get(0).getIconName(), IconModel.DEFAULT_ICON_SIZE));
-                    label.setForeground(aliases.get(0).getDisplayColor());
+                    label.setForeground(ThemeManager.getInstance().getReadableColor(aliases.get(0).getDisplayColor(),
+                        label.getBackground()));
                 }
                 else
                 {

src/main/java/io/github/dsheirer/channel/metadata/NowPlayingPanel.java

@@ -28,7 +28,6 @@ import io.github.dsheirer.module.decode.event.MessageActivityPanel;
 import io.github.dsheirer.playlist.PlaylistManager;
 import io.github.dsheirer.preference.UserPreferences;
 import io.github.dsheirer.settings.SettingsManager;
-import java.awt.Color;
 import net.miginfocom.swing.MigLayout;
 
 import javax.swing.JPanel;
@@ -98,7 +97,6 @@ public class NowPlayingPanel extends JPanel
             mTabbedPane.addTab("Messages", mMessageActivityPanel);
             mTabbedPane.addTab("Channel", mChannelSpectrumSquelchPanel);
             mTabbedPane.setFont(this.getFont());
-            mTabbedPane.setForeground(Color.BLACK);
             //Register state change listener to toggle visibility state for channel tab to turn-on/off FFT processing
             mTabbedPane.addChangeListener(e -> mChannelSpectrumSquelchPanel.setPanelVisible(getTabbedPane().getSelectedIndex() == getTabbedPane()
                     .indexOfComponent(mChannelSpectrumSquelchPanel)));

src/main/java/io/github/dsheirer/channel/state/DecoderState.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2024 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

src/main/java/io/github/dsheirer/channel/state/MultiChannelState.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2024 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -523,19 +523,6 @@ public class MultiChannelState extends AbstractChannelState implements IDecoderS
                             FrequencyConfigurationIdentifier.create(frequency), IdentifierUpdateNotification.Operation.SILENT_ADD, timeslot));
                     }
 
-                    break;
-                case NOTIFICATION_MEASURED_FREQUENCY_ERROR:
-                    //Rebroadcast frequency error measurements to external listener if we're currently
-                    //in an active (ie sync locked) state.
-                    for(int timeslot: mTimeslots)
-                    {
-                        if(State.MULTI_CHANNEL_ACTIVE_STATES.contains(mStateMachineMap.get(timeslot).getState()))
-                        {
-                            broadcast(SourceEvent.frequencyErrorMeasurementSyncLocked(sourceEvent.getValue().longValue(),
-                                getChannel().getChannelType().name()));
-                            return;
-                        }
-                    }
                     break;
             }
         }

src/main/java/io/github/dsheirer/channel/state/SingleChannelState.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2024 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -26,6 +26,7 @@ import io.github.dsheirer.channel.state.DecoderStateEvent.Event;
 import io.github.dsheirer.controller.channel.Channel;
 import io.github.dsheirer.controller.channel.ChannelConfigurationChangeNotification;
 import io.github.dsheirer.controller.channel.ChannelEvent;
+import io.github.dsheirer.identifier.Identifier;
 import io.github.dsheirer.identifier.IdentifierClass;
 import io.github.dsheirer.identifier.IdentifierUpdateListener;
 import io.github.dsheirer.identifier.IdentifierUpdateNotification;
@@ -46,6 +47,7 @@ import io.github.dsheirer.source.SourceEvent;
 import io.github.dsheirer.source.SourceType;
 import io.github.dsheirer.source.config.SourceConfigTuner;
 import io.github.dsheirer.source.config.SourceConfigTunerMultipleFrequency;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import org.slf4j.Logger;
@@ -217,28 +219,45 @@ public class SingleChannelState extends AbstractChannelState implements IDecoder
      */
     private void createConfigurationIdentifiers(Channel channel)
     {
-        mIdentifierCollection.update(DecoderTypeConfigurationIdentifier.create(channel.getDecodeConfiguration().getDecoderType()));
+        List<Identifier<?>> identifiers = createChannelIdentifiers(channel);
+
+        for(Identifier<?> identifier : identifiers)
+        {
+            mIdentifierCollection.update(identifier);
+        }
+    }
+
+    /**
+     * Creates channel metadata identifiers.
+     * @param channel to process
+     * @return list of identifiers
+     */
+    public static List<Identifier<?>> createChannelIdentifiers(Channel channel)
+    {
+        List<Identifier<?>> identifiers = new ArrayList<>();
+
+        identifiers.add(DecoderTypeConfigurationIdentifier.create(channel.getDecodeConfiguration().getDecoderType()));
 
         if(channel.hasSystem())
         {
-            mIdentifierCollection.update(SystemConfigurationIdentifier.create(channel.getSystem()));
+            identifiers.add(SystemConfigurationIdentifier.create(channel.getSystem()));
         }
         if(channel.hasSite())
         {
-            mIdentifierCollection.update(SiteConfigurationIdentifier.create(channel.getSite()));
+            identifiers.add(SiteConfigurationIdentifier.create(channel.getSite()));
         }
         if(channel.getName() != null && !channel.getName().isEmpty())
         {
-            mIdentifierCollection.update(ChannelNameConfigurationIdentifier.create(channel.getName()));
+            identifiers.add(ChannelNameConfigurationIdentifier.create(channel.getName()));
         }
         if(channel.getAliasListName() != null && !channel.getAliasListName().isEmpty())
         {
-            mIdentifierCollection.update(AliasListConfigurationIdentifier.create(channel.getAliasListName()));
+            identifiers.add(AliasListConfigurationIdentifier.create(channel.getAliasListName()));
         }
         if(channel.getSourceConfiguration().getSourceType() == SourceType.TUNER)
         {
             long frequency = ((SourceConfigTuner)channel.getSourceConfiguration()).getFrequency();
-            mIdentifierCollection.update(FrequencyConfigurationIdentifier.create(frequency));
+            identifiers.add(FrequencyConfigurationIdentifier.create(frequency));
         }
         else if(channel.getSourceConfiguration().getSourceType() == SourceType.TUNER_MULTIPLE_FREQUENCIES)
         {
@@ -246,9 +265,11 @@ public class SingleChannelState extends AbstractChannelState implements IDecoder
 
             if(frequencies.size() > 0)
             {
-                mIdentifierCollection.update(FrequencyConfigurationIdentifier.create(frequencies.get(0)));
+                identifiers.add(FrequencyConfigurationIdentifier.create(frequencies.get(0)));
             }
         }
+
+        return identifiers;
     }
 
     /**
@@ -392,15 +413,6 @@ public class SingleChannelState extends AbstractChannelState implements IDecoder
                     mIdentifierUpdateNotificationProxy.receive(new IdentifierUpdateNotification(
                         FrequencyConfigurationIdentifier.create(frequency), IdentifierUpdateNotification.Operation.SILENT_ADD, 0));
                     break;
-                case NOTIFICATION_MEASURED_FREQUENCY_ERROR:
-                    //Rebroadcast frequency error measurements to external listener if we're currently
-                    //in an active (ie sync locked) state.
-                    if(State.SINGLE_CHANNEL_ACTIVE_STATES.contains(mStateMachine.getState()))
-                    {
-                        broadcast(SourceEvent.frequencyErrorMeasurementSyncLocked(sourceEvent.getValue().longValue(),
-                            getChannel().getChannelType().name()));
-                    }
-                    break;
             }
         }
     }
@@ -421,9 +433,8 @@ public class SingleChannelState extends AbstractChannelState implements IDecoder
                         mSquelchController.setSquelchLock(true);
                         break;
                     case REQUEST_CHANGE_CALL_TIMEOUT:
-                        if(event instanceof ChangeChannelTimeoutEvent)
+                        if(event instanceof ChangeChannelTimeoutEvent timeout)
                         {
-                            ChangeChannelTimeoutEvent timeout = (ChangeChannelTimeoutEvent)event;
                             mStateMachine.setFadeTimeoutBufferMilliseconds(timeout.getCallTimeoutMilliseconds());
                         }
                     case CONTINUATION:
@@ -471,7 +482,7 @@ public class SingleChannelState extends AbstractChannelState implements IDecoder
      * Proxy between the internal identifier collection and the external update notification listener.  This proxy
      * enables access to internal components to broadcast silent identifier update notifications externally.
      */
-    public class IdentifierUpdateNotificationProxy implements Listener<IdentifierUpdateNotification>
+    public static class IdentifierUpdateNotificationProxy implements Listener<IdentifierUpdateNotification>
     {
         private Listener<IdentifierUpdateNotification> mIdentifierUpdateNotificationListener;
 

src/main/java/io/github/dsheirer/channel/state/TimeslotDecoderState.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- * Copyright (C) 2014-2024 Dennis Sheirer
+ * Copyright (C) 2014-2025 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -19,7 +19,7 @@
 
 package io.github.dsheirer.channel.state;
 
-import io.github.dsheirer.channel.IChannelDescriptor;
+import io.github.dsheirer.channel.IBandChannelDescriptor;
 import io.github.dsheirer.identifier.Form;
 import io.github.dsheirer.identifier.Identifier;
 import io.github.dsheirer.identifier.IdentifierClass;
@@ -89,9 +89,9 @@ public abstract class TimeslotDecoderState extends DecoderState
                     {
                         setCurrentChannel(((ChannelDescriptorConfigurationIdentifier)identifier).getValue());
                     }
-                    else if(identifier instanceof IChannelDescriptor)
+                    else if(identifier instanceof IBandChannelDescriptor)
                     {
-                        setCurrentChannel((IChannelDescriptor)identifier);
+                        setCurrentChannel((IBandChannelDescriptor)identifier);
                     }
                     else if(identifier instanceof FrequencyConfigurationIdentifier fci)
                     {

src/main/java/io/github/dsheirer/controller/ControllerPanel.java

@@ -32,10 +32,9 @@ import io.github.dsheirer.preference.UserPreferences;
 import io.github.dsheirer.settings.SettingsManager;
 import io.github.dsheirer.source.tuner.manager.TunerManager;
 import io.github.dsheirer.source.tuner.ui.TunerViewPanel;
-import java.awt.Color;
 import java.awt.Dimension;
 import jiconfont.icons.font_awesome.FontAwesome;
-import jiconfont.swing.IconFontSwing;
+import io.github.dsheirer.gui.theme.ThemedFontIcon;
 import net.miginfocom.swing.MigLayout;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -100,12 +99,11 @@ public class ControllerPanel extends JPanel
             }
         };
         mTabbedPane.setFont(this.getFont());
-        mTabbedPane.setForeground(Color.BLACK);
         mTabbedPane.addTab("Now Playing", mNowPlayingPanel);
         mTabbedPane.addTab("Map", mMapPanel);
         mTabbedPane.addTab("Tuners", mTunerManagerPanel);
 
-        Icon playIcon = IconFontSwing.buildIcon(FontAwesome.PLAY_CIRCLE_O, 20, Color.DARK_GRAY);
+        Icon playIcon = new ThemedFontIcon(FontAwesome.PLAY_CIRCLE_O, 20);
         mTabbedPane.addTab("Playlist Editor", playIcon, new JLabel("Show Playlist Manager"));
         mSettingsTabIndex = mTabbedPane.getTabCount() - 1;
 

src/main/java/io/github/dsheirer/controller/channel/ChannelProcessingManager.java

@@ -418,6 +418,11 @@ public class ChannelProcessingManager implements Listener<ChannelEvent>
             throw new ChannelException("No Tuner Available");
         }
 
+        if(source instanceof TunerChannelSource tunerChannelSource)
+        {
+            tunerChannelSource.setStartTimestamp(request.getStartTimestamp());
+        }
+
         ProcessingChain processingChain = new ProcessingChain(channel, mAliasModel);
 
         //Certain decoders aggregate the decode events in the parent channel that also includes any events produced

src/main/java/io/github/dsheirer/controller/channel/event/ChannelStartProcessingRequest.java

@@ -1,6 +1,6 @@
 /*
  * *****************************************************************************
- *  Copyright (C) 2014-2020 Dennis Sheirer
+ * Copyright (C) 2014-2026 Dennis Sheirer
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -19,13 +19,13 @@
 
 package io.github.dsheirer.controller.channel.event;
 
+import io.github.dsheirer.channel.IBandChannelDescriptor;
 import io.github.dsheirer.channel.IChannelDescriptor;
 import io.github.dsheirer.controller.channel.Channel;
 import io.github.dsheirer.identifier.IdentifierCollection;
 import io.github.dsheirer.module.ModuleEventBusMessage;
 import io.github.dsheirer.module.decode.event.DecodeEventHistory;
 import io.github.dsheirer.module.decode.traffic.TrafficChannelManager;
-
 import java.util.ArrayList;
 import java.util.List;
 
@@ -42,6 +42,7 @@ public class ChannelStartProcessingRequest extends ModuleEventBusMessage
     private DecodeEventHistory mParentDecodeEventHistory;
     private DecodeEventHistory mChildDecodeEventHistory;
     private boolean mPersistentAttempt;
+    private long mStartTimestamp;
 
     /**
      * Constructs an instance
@@ -66,7 +67,7 @@ public class ChannelStartProcessingRequest extends ModuleEventBusMessage
      * @param channelDescriptor that identifies which channel in a multi-channel config to start
      * @param identifierCollection to use for the new channel
      */
-    public ChannelStartProcessingRequest(Channel channel, IChannelDescriptor channelDescriptor,
+    public ChannelStartProcessingRequest(Channel channel, IBandChannelDescriptor channelDescriptor,
                                          IdentifierCollection identifierCollection)
     {
         this(channel, channelDescriptor, identifierCollection, null);
@@ -109,6 +110,25 @@ public class ChannelStartProcessingRequest extends ModuleEventBusMessage
         return mPersistentAttempt;
     }
 
+    /**
+     * Sets the timestamp of the channel grant so that a tuner channel source with a sample delay buffer can preload the
+     * channel with the samples that occurred after the grant, while the grant was being decoded and processed.
+     * @param timestamp of the channel grant in milliseconds since epoch.
+     */
+    public void setStartTimestamp(long timestamp)
+    {
+        mStartTimestamp = timestamp;
+    }
+
+    /**
+     * Timestamp for the oldest samples requested for the channel.
+     * @return timestamp in milliseconds since epoch, or 0 if the channel should start with current samples.
+     */
+    public long getStartTimestamp()
+    {
+        return mStartTimestamp;
+    }
+
     /**
      * Channel to start processing
      * @return channel to start

src/main/java/io/github/dsheirer/dsp/c4fm/C4FMEqualizer.java

@@ -0,0 +1,375 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2026 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+
+package io.github.dsheirer.dsp.c4fm;
+
+import io.github.dsheirer.dsp.symbol.Dibit;
+import java.text.DecimalFormat;
+import java.util.Arrays;
+import org.apache.commons.math3.stat.descriptive.moment.Variance;
+
+/**
+ * LMS adaptive equalizer for real-valued C4FM symbols.  Trains taps on externally triggered sync detection combined
+ * with dynamic tap updates for a fixed symbol count and then freezes the taps until the error variance between sync
+ * detections exceeds a fixed threshold, whereby a tap retraining is enqueued for the next sync detection.
+ */
+public class C4FMEqualizer
+{
+    private static final DecimalFormat DF = new DecimalFormat("0.0000");
+    //Maximum possible error is PI/4 = 0.78, but we clip it to less than half as the allowable error for tap updates
+    private static final float MAX_SYMBOL_ERROR = 0.3f;
+    private static final double TRAINING_IMPROVEMENT_GOAL_PER_ITERATION = 0.0005f;
+    private static final double TRAINING_CONVERGENCE_THRESHOLD = 0.16f;
+    private static final double TRAINING_SKIP_VARIANCE_THRESHOLD = 0.05;
+    private static final int TRAINING_ITERATIONS_MAX = 30;
+    private final Variance mVariance = new Variance();
+    private final float[] mBuffer;
+    private final float[] mReversedSyncSymbols;
+    private final float[] mTaps;
+    private final int mCenterTap;
+    private final int mDelaySymbolCount;
+    private final int mTrainingPeriodSymbolCount;
+    private final int mTrainingSkipCountThreshold;
+    private boolean mEnabled = false;
+    private boolean mSyncDetected = false;
+    private int mSymbolsUntilTraining = 0;
+    private int mTrainingSymbolsRemaining = 0;
+    private int mSkippedTrainingCount = 0;
+
+    /**
+     * Constructs an instance with an equalizer length derived from the sync pattern length.
+     *
+     * @param syncSymbols sync pattern that will be used to train the equalizer on sync detections
+     * @param trainingPeriodSymbolCount following sync detection to continue training.
+     * @param maxNoTrainSyncCount maximum number of consecutive sync detections and skipped trainings that can occur without retraining.
+     */
+    public C4FMEqualizer(float[] syncSymbols, int trainingPeriodSymbolCount, int maxNoTrainSyncCount)
+    {
+        this(syncSymbols, getDefaultSymbolLength(syncSymbols.length), trainingPeriodSymbolCount, maxNoTrainSyncCount);
+    }
+
+    /**
+     * Constructs an instance
+     *
+     * @param syncSymbols sync pattern that will be used to train the equalizer on sync detections
+     * @param equalizerSymbolLength equalizer span in symbols.  Even values are reduced by one so that the center tap
+     * has equal delay on either side.  The tap count is twice this value since this is a fractional (T/2) equalizer.
+     * @param trainingPeriodSymbolCount following sync detection to continue training.
+     * @param maxNoTrainSyncCount maximum number of consecutive sync detections and skipped trainings that can occur without retraining.
+     */
+    public C4FMEqualizer(float[] syncSymbols, int equalizerSymbolLength, int trainingPeriodSymbolCount,
+                         int maxNoTrainSyncCount)
+    {
+        if(equalizerSymbolLength < 1)
+        {
+            throw new IllegalArgumentException("Equalizer symbol length must be at least 1");
+        }
+
+        //Store the sync pattern in reverse order
+        mReversedSyncSymbols = new float[syncSymbols.length];
+        for(int x = 0; x < syncSymbols.length; x++)
+        {
+            mReversedSyncSymbols[syncSymbols.length - x - 1] = syncSymbols[x];
+        }
+
+        //Make the symbol count odd length for equal delay on either side of the center tap
+        int symbolLength = (equalizerSymbolLength % 2 == 0) ? equalizerSymbolLength - 1 : equalizerSymbolLength;
+        mCenterTap = symbolLength; //This works since we're going to double the buffer length
+        mDelaySymbolCount = symbolLength / 2; //Delay until new symbol is aligned to center tap
+        mTaps = new float[symbolLength * 2];
+        mTaps[mCenterTap] = 1.0f;
+        int bufferLength = mReversedSyncSymbols.length * 2 + mTaps.length - 2;
+        mBuffer = new float[bufferLength];
+        mTrainingPeriodSymbolCount = trainingPeriodSymbolCount;
+        mTrainingSkipCountThreshold = maxNoTrainSyncCount;
+    }
+
+    /**
+     * Default equalizer span in symbols derived from the sync pattern length (odd length).
+     * @param syncLength in symbols
+     * @return default equalizer symbol length
+     */
+    public static int getDefaultSymbolLength(int syncLength)
+    {
+        return (syncLength % 2 == 0) ? syncLength - 1 : syncLength;
+    }
+
+    /**
+     * Description of the current tap values
+     */
+    public String getTapsDescription()
+    {
+        StringBuilder sb = new StringBuilder();
+        sb.append("<html>EQ Taps<br>");
+        for(int i = 0; i < mTaps.length; i++)
+        {
+            sb.append(i).append(": ").append(DF.format(mTaps[i])).append("<br>");
+        }
+
+        return sb.toString();
+    }
+
+    /**
+     * Symbol processing delay.
+     * @return processing delay in symbols.
+     */
+    public int getDelaySymbolCount()
+    {
+        return mDelaySymbolCount;
+    }
+
+    /**
+     * Length of the equalizer in symbols.  Note: the internal tap count is twice as long since this
+     * is a fractional (x2) equalizer.
+     * @return length in symbols.
+     */
+    public int getLength()
+    {
+        return mTaps.length / 2;
+    }
+
+    /**
+     * Enable the equalizer when a valid sync pattern is detected
+     */
+    public void enable()
+    {
+        mEnabled = true;
+    }
+
+    /**
+     * Indicates the enabled state.
+     * @return enabled state
+     */
+    public boolean isEnabled()
+    {
+        return mEnabled;
+    }
+
+    /**
+     * Disable the equalizer when the signal is lost so that noise doesn't contaminate the equalizer taps.
+     */
+    public void disable()
+    {
+        mEnabled = false;
+    }
+
+    /**
+     * Notifies the equalizer that a sync pattern is detected and queues a training sequence once a couple more
+     * symbols arrive once the equalizer delay line has aligned to output the sync pattern.
+     */
+    public void syncDetected()
+    {
+        mSyncDetected = true;
+        mSymbolsUntilTraining = mDelaySymbolCount;
+    }
+
+    /**
+     * Notifies the equalizer that a sync pattern is detected and updates the sync pattern used for training.  This
+     * supports protocols (ie DMR) that employ multiple sync patterns of the same length.
+     * @param syncSymbols for the detected sync pattern, which must be the same length as the constructor sync pattern.
+     */
+    public void syncDetected(float[] syncSymbols)
+    {
+        if(syncSymbols.length != mReversedSyncSymbols.length)
+        {
+            throw new IllegalArgumentException("Sync symbols length [" + syncSymbols.length +
+                    "] must match the equalizer sync pattern length [" + mReversedSyncSymbols.length + "]");
+        }
+
+        for(int x = 0; x < syncSymbols.length; x++)
+        {
+            mReversedSyncSymbols[syncSymbols.length - x - 1] = syncSymbols[x];
+        }
+
+        syncDetected();
+    }
+
+    /**
+     * Indicates that the sync patter is lost and the equalizer should reset.
+     */
+    public void syncLost()
+    {
+//        System.out.println("C4FM Equalizer - sync lost triggered");
+        reset();
+        disable();
+    }
+
+    /*
+     * Resets the equalizer taps
+     */
+    public void reset()
+    {
+        Arrays.fill(mTaps, 0f);
+        mTaps[mCenterTap] = 1.0f;
+        mVariance.clear();
+    }
+
+    /**
+     * Process the samples and produce a delayed, equalized soft symbol ready for symbol decision.  Updates the
+     * equalizer taps to correct for the error in the equalized sample relative to the hard symbol decision.
+     *
+     * @param fractional sample that falls halfway between symbols
+     * @param symbol to equalize
+     * @return equalized symbol.
+     */
+    public float process(float fractional, float symbol)
+    {
+        //Shift buffer samples to the right two places and add new sample and symbol.
+        System.arraycopy(mBuffer, 0, mBuffer, 2, mBuffer.length - 2);
+        mBuffer[0] = fractional;
+        mBuffer[1] = symbol;
+
+        //Since there's a buffer delay, count down from sync detection until the pattern is aligned with the buffer
+        // contents and we can start training
+        if(mSyncDetected)
+        {
+            if(--mSymbolsUntilTraining <= 0)
+            {
+                train();
+            }
+        }
+
+        float equalized = 0f;
+
+        if(mEnabled)
+        {
+            int tapIndex;
+
+            for(tapIndex = 0; tapIndex < mTaps.length; tapIndex++)
+            {
+                equalized += mTaps[tapIndex] * mBuffer[tapIndex];
+            }
+
+            if(mTrainingSymbolsRemaining > 0)
+            {
+                mTrainingSymbolsRemaining--;
+                float error = Dibit.getError(equalized);
+                error = Math.clamp(error, -MAX_SYMBOL_ERROR, MAX_SYMBOL_ERROR);
+
+                //Step size (mu) in range 0.0001 to 0.01
+                float stepSize = 0.01f;
+
+                for(tapIndex = 0; tapIndex < mTaps.length; tapIndex++)
+                {
+                    if(tapIndex != mCenterTap)
+                    {
+                        mTaps[tapIndex] += stepSize * error * mBuffer[tapIndex];
+                    }
+                }
+            }
+
+            //Track the residual error that remains after equalization
+            mVariance.increment(Dibit.getError(equalized));
+        }
+        else
+        {
+            //Return the uncorrected, delayed symbol when we're disabled
+            equalized = mBuffer[mCenterTap];
+        }
+
+        return equalized;
+    }
+
+    /**
+     * Trains the equalizer against the buffered detected sync pattern.  Trains against the sync pattern sequence
+     * multiple times while the per-iteration improvement continues to become smaller and stops training once the
+     * improvement falls below a threshold goal or exceeds a maximum iterations.  If the training converges to
+     * below a threshold, we snapshot and use the trained taps, otherwise fallback to the previous training snapshot.
+     */
+    private void train()
+    {
+        mSyncDetected = false;
+
+        //Skip retrain when we're still doing dynamic tap adjustments following the previous training session.
+        if(mTrainingSymbolsRemaining > 0)
+        {
+            mVariance.clear();
+            return;
+        }
+
+//        System.out.println("**C4FM EQ Training Triggered - skip count[" + mSkippedTrainingCount + "] variance [" + mVariance.getResult() + "] var threshold [" + TRAINING_SKIP_VARIANCE_THRESHOLD + "]");
+
+        //Ensure we've collected enough variance samples in the buffer and we have sufficient variance
+        if(mVariance.getN() <= mDelaySymbolCount || mVariance.getResult() > TRAINING_SKIP_VARIANCE_THRESHOLD ||
+                ++mSkippedTrainingCount > mTrainingSkipCountThreshold)
+        {
+            mSkippedTrainingCount = 0;
+            //If the current variance tracked since the last training session using dynamic tap adjustments at each
+            // symbol is excessive, fallback to the most recent training snapshot as a better starting point
+            if(mVariance.getResult() > 0.225)
+            {
+                reset();
+            }
+
+            float accumulator, error;
+            double improvement, previousVariance;
+            int symbolIndex, index, trainingIterationCount = 0;
+            Variance variance = new Variance();
+
+            //Step size (mu) in range 0.0001 to 0.01
+            float stepSize = 0.005f;
+
+            do
+            {
+                previousVariance = variance.getN() == 0 ? 20.0 : variance.getResult();
+                variance.clear();
+
+
+                for(symbolIndex = 0; symbolIndex < mReversedSyncSymbols.length; symbolIndex++)
+                {
+                    accumulator = 0.0f;
+                    for(index = 0; index < mTaps.length; index++)
+                    {
+                        accumulator += mTaps[index] * mBuffer[index + (2 * symbolIndex)];
+                    }
+
+                    error = mReversedSyncSymbols[symbolIndex] - accumulator;
+                    variance.increment(error);
+
+                    for(index = 0; index < mTaps.length; index++)
+                    {
+                        if(index != mCenterTap)
+                        {
+                            mTaps[index] += error * stepSize * mBuffer[index + (2 * symbolIndex)];
+                        }
+                    }
+                }
+
+                trainingIterationCount++;
+                improvement = previousVariance - variance.getResult();
+            }
+            while(trainingIterationCount < TRAINING_ITERATIONS_MAX && improvement > TRAINING_IMPROVEMENT_GOAL_PER_ITERATION);
+
+//            System.out.println("**C4FM EQ - train complete - iterations [" + trainingIterationCount +
+//                    "] end variance [" + DF.format(variance.getResult()) +
+//                    "] final improvement [" + DF.format(improvement) +
+//                    "] improvement threshold [" + DF.format(TRAINING_IMPROVEMENT_GOAL_PER_ITERATION) + "]");
+
+            //If we failed to converge, reset the taps to default and use blind training
+            if(variance.getResult() > TRAINING_CONVERGENCE_THRESHOLD)
+            {
+                reset();
+            }
+
+            mTrainingSymbolsRemaining = mTrainingPeriodSymbolCount;
+        }
+
+        mVariance.clear();
+    }
+}

src/main/java/io/github/dsheirer/dsp/c4fm/C4FMMessageFramer.java

@@ -0,0 +1,68 @@
+package io.github.dsheirer.dsp.c4fm;
+
+import io.github.dsheirer.dsp.symbol.Dibit;
+
+/**
+ * C4FM message framer base class.
+ */
+public abstract class C4FMMessageFramer
+{
+    private static final float SOFT_SYMBOL_SCALE = (float)(4.0 / Math.PI); //Radians to symbol units (+/-1, +/-3)
+
+    /**
+     * Converts the soft symbol into a pair of soft bit values using max-log likelihood ratios for the Gray mapped
+     * 4-level symbol (D01=+3, D00=+1, D10=-1, D11=-3), where a positive soft bit value favors a 1 bit.
+     * @param softSymbol in radians
+     * @param softBits array to receive the two soft bit values
+     * @param index for the first bit (sign bit), followed by the second (magnitude) bit
+     */
+    protected static void setSoftBits(float softSymbol, float[] softBits, int index)
+    {
+        float u = softSymbol * SOFT_SYMBOL_SCALE;
+        float magnitude = Math.abs(u);
+        //First bit is 1 for negative symbols
+        float favorZero = magnitude <= 2.0f ? 4.0f * u : 8.0f * u - 8.0f * Math.signum(u);
+        softBits[index] = -favorZero;
+        //Second bit is 1 for the outer (+/-3) symbols
+        softBits[index + 1] = 4.0f * (magnitude - 2.0f);
+    }
+
+    /**
+     * Process the symbol
+     * @param symbol in radians
+     * @return true if the framer emits a valid message that includes this symbol, so that corrective measurement
+     * can be sent to a feedback decoder.
+     */
+    public abstract boolean process(Dibit symbol);
+
+    /**
+     * Process the symbol decision along with the soft symbol it was decided from.  Framers that can use soft symbols
+     * (ie soft decision decoding) override this method.  Default implementation discards the soft symbol.
+     * @param symbol decision
+     * @param softSymbol equalized soft symbol in radians
+     * @return true if the framer emits a valid message that includes this symbol.
+     */
+    public boolean process(Dibit symbol, float softSymbol)
+    {
+        return process(symbol);
+    }
+
+    /**
+     * Process the symbol decision along with the soft symbol it was decided from and the soft symbol reliability (ie
+     * inverse of the soft symbol noise variance).  Framers that can weight soft decision decoding override this method.
+     * Default implementation discards the reliability.
+     * @param symbol decision
+     * @param softSymbol equalized soft symbol in radians
+     * @param reliability of the soft symbol
+     * @return true if the framer emits a valid message that includes this symbol.
+     */
+    public boolean process(Dibit symbol, float softSymbol, float reliability)
+    {
+        return process(symbol, softSymbol);
+    }
+
+    /**
+     * A sync pattern is detected
+     */
+    public abstract void syncDetected();
+}