diff --git a/src/main/java/io/github/dsheirer/instrument/gui/viewer/ComplexPhaseLineChart.java b/src/main/java/io/github/dsheirer/instrument/gui/viewer/ComplexPhaseLineChart.java
index 08189c93..9ec6d77f 100644
--- a/src/main/java/io/github/dsheirer/instrument/gui/viewer/ComplexPhaseLineChart.java
+++ b/src/main/java/io/github/dsheirer/instrument/gui/viewer/ComplexPhaseLineChart.java
@@ -115,7 +115,7 @@ public class ComplexPhaseLineChart extends LineChart implements Listener<Complex
                 previous.add(ANGLE_OFFSET_45_DEGREES);
                 sample.multiply(previous.conjugate());
 //                sample.normalize();
-                mPhaseValues.get(x - 10).setYValue(sample.angle());
+                mPhaseValues.get(x - 9).setYValue(sample.angle());
             }
         }
     }
diff --git a/src/main/java/io/github/dsheirer/instrument/gui/viewer/DemodulatorViewerFX.java b/src/main/java/io/github/dsheirer/instrument/gui/viewer/DemodulatorViewerFX.java
index a3d6776e..d46e5463 100644
--- a/src/main/java/io/github/dsheirer/instrument/gui/viewer/DemodulatorViewerFX.java
+++ b/src/main/java/io/github/dsheirer/instrument/gui/viewer/DemodulatorViewerFX.java
@@ -37,7 +37,7 @@ public class DemodulatorViewerFX extends Application
 {
     private Stage mStage;
     private MenuBar mMenuBar;
-    private RecentFilesMenuItem mRecentFilesMenuItem;
+    private RecentFilesMenu mRecentFilesMenu;
     private ViewerDesktop mViewerDesktop;
 
     @Override
@@ -83,7 +83,7 @@ public class DemodulatorViewerFX extends Application
                     fileChooser.setTitle("Open an I/Q recording file");
                     File file = fileChooser.showOpenDialog(mStage);
                     getViewerDesktop().load(file);
-                    getRecentFilesMenuItem().add(file);
+                    getRecentFilesMenu().add(file);
                 }
             });
 
@@ -107,9 +107,7 @@ public class DemodulatorViewerFX extends Application
                 }
             });
 
-            mRecentFilesMenuItem = new RecentFilesMenuItem("demodulator.viewer", 5);
-
-            menuFile.getItems().addAll(menuItemOpen, getRecentFilesMenuItem(), menuItemClose, new SeparatorMenuItem(),
+            menuFile.getItems().addAll(menuItemOpen, getRecentFilesMenu(), menuItemClose, new SeparatorMenuItem(),
                     menuItemExit);
 
             mMenuBar.getMenus().addAll(menuFile);
@@ -118,12 +116,12 @@ public class DemodulatorViewerFX extends Application
         return mMenuBar;
     }
 
-    private RecentFilesMenuItem getRecentFilesMenuItem()
+    private RecentFilesMenu getRecentFilesMenu()
     {
-        if(mRecentFilesMenuItem == null)
+        if(mRecentFilesMenu == null)
         {
-            mRecentFilesMenuItem = new RecentFilesMenuItem("demodulator.viewer", 5);
-            mRecentFilesMenuItem.setFileSelectionListener(new RecentFilesMenuItem.IFileSelectionListener()
+            mRecentFilesMenu = new RecentFilesMenu("Recent","demodulator.viewer", 5);
+            mRecentFilesMenu.setFileSelectionListener(new RecentFilesMenu.IFileSelectionListener()
             {
                 @Override
                 public void fileSelected(File file)
@@ -133,7 +131,7 @@ public class DemodulatorViewerFX extends Application
             });
         }
 
-        return mRecentFilesMenuItem;
+        return mRecentFilesMenu;
     }
 
     public static void main(String[] args)
diff --git a/src/main/java/io/github/dsheirer/instrument/gui/viewer/PlaybackController.java b/src/main/java/io/github/dsheirer/instrument/gui/viewer/PlaybackController.java
index d615135c..94a958f2 100644
--- a/src/main/java/io/github/dsheirer/instrument/gui/viewer/PlaybackController.java
+++ b/src/main/java/io/github/dsheirer/instrument/gui/viewer/PlaybackController.java
@@ -67,6 +67,7 @@ public class PlaybackController extends HBox implements IFrameLocationListener,
 
     public void load(File file)
     {
+        mLog.debug("loading:" + file.getAbsolutePath());
         if(file != null && file.isFile())
         {
             try
@@ -112,6 +113,8 @@ public class PlaybackController extends HBox implements IFrameLocationListener,
                 mLog.error("Error closing file", ioe);
             }
         }
+
+        setControlsEnabled(false);
     }
 
     /**
diff --git a/src/main/java/io/github/dsheirer/instrument/gui/viewer/RecentFilesMenu.java b/src/main/java/io/github/dsheirer/instrument/gui/viewer/RecentFilesMenu.java
new file mode 100644
index 00000000..873babf7
--- /dev/null
+++ b/src/main/java/io/github/dsheirer/instrument/gui/viewer/RecentFilesMenu.java
@@ -0,0 +1,192 @@
+package io.github.dsheirer.instrument.gui.viewer;
+
+import javafx.event.ActionEvent;
+import javafx.event.EventHandler;
+import javafx.scene.control.Menu;
+import javafx.scene.control.MenuItem;
+import javafx.scene.control.SeparatorMenuItem;
+
+import java.io.File;
+import java.util.prefs.Preferences;
+
+public class RecentFilesMenu extends Menu implements EventHandler<ActionEvent>
+{
+    private Preferences mPreferences = Preferences.userNodeForPackage(RecentFilesMenu.class);
+    private IFileSelectionListener mFileSelectionListener;
+    private String mIdentifier;
+    private int mSize;
+
+    /**
+     * Recently used files menu.  Uses java Preferences to store recently accessed files and provides access to those
+     * files via child menu items to this menu.
+     *
+     * @param label to use for this menu.
+     * @param uniqueIdentifier to use in addition to the class path of this class to uniquely identify recently accessed
+     * files in a java Preferences data store.
+     * @param size of the maximum number of recent files to present to the user
+     */
+    public RecentFilesMenu(String label, String uniqueIdentifier, int size)
+    {
+        super(label);
+        mIdentifier = uniqueIdentifier;
+        mSize = size;
+
+        load();
+    }
+
+    /**
+     * Registers the listener to receive file selection events when the user selects a recently used file.
+     * @param listener to receive file selection events
+     */
+    public void setFileSelectionListener(IFileSelectionListener listener)
+    {
+        mFileSelectionListener = listener;
+    }
+
+    /**
+     * Adds the file to the recently accessed files list.  If this file is already included in the recently files list,
+     * it will be promoted to the first menu item and all other recently used files will be demoted.
+     *
+     * @param file to add to the recently used files list.
+     */
+    public void add(File file)
+    {
+        if(file != null)
+        {
+            String filePath = file.getAbsolutePath();
+
+            int index = mSize - 1;
+
+            //Check to see if this file is already in the recent files list
+            for(int x = mSize - 1; x >= 0; x--)
+            {
+                String existingItem = mPreferences.get(getKey(x), null);
+
+                if(existingItem != null && existingItem.equals(filePath))
+                {
+                    index = x;
+                    break;
+                }
+            }
+
+            //Shift all recent files down to make room for the newly added file at the top of the list
+            while(index > 0)
+            {
+                String newerItem = mPreferences.get(getKey(index - 1), null);
+
+                if(newerItem != null)
+                {
+                    mPreferences.put(getKey(index), newerItem);
+                }
+
+                index--;
+            }
+
+            mPreferences.put(getKey(0), file.getAbsolutePath());
+        }
+
+        load();
+    }
+
+    /**
+     * Creates a unique key value for each numbered recently used file item in the preferences.
+     *
+     * @param index of recent file item.
+     * @return unique key to use with the preferences instance.
+     */
+    private String getKey(int index)
+    {
+        return mIdentifier + ".recent.file." + index;
+    }
+
+    /**
+     * Clears and (re)loads all child recent file menu items.
+     */
+    private void load()
+    {
+        getItems().clear();
+
+        for(int x = 0; x < mSize; x++)
+        {
+            String path = mPreferences.get(getKey(x), null);
+
+            if(path != null)
+            {
+                File file = new File(path);
+
+                if(file.isFile())
+                {
+                    MenuItem menuItem = new MenuItem(file.getName());
+                    menuItem.setUserData(file);
+                    menuItem.setOnAction(this);
+                    getItems().add(menuItem);
+                }
+            }
+        }
+
+        if(getItems().size() > 0)
+        {
+            setDisable(false);
+            getItems().add(new SeparatorMenuItem());
+
+            MenuItem clearMenuItem = new MenuItem("Clear History");
+            clearMenuItem.setOnAction(new EventHandler<ActionEvent>()
+            {
+                @Override
+                public void handle(ActionEvent event)
+                {
+                    clearHistory();
+                }
+            });
+            getItems().add(clearMenuItem);
+        }
+        else
+        {
+            setDisable(true);
+        }
+    }
+
+    /**
+     * Clears the recently used files history and removes all items from the preferences instance
+     */
+    private void clearHistory()
+    {
+        for(int x = 0; x < mSize; x++)
+        {
+            mPreferences.remove(getKey(x));
+        }
+
+        load();
+    }
+
+    /**
+     * Event handler for all recent file child menu items.  Extracts the selected file stored as the user data object
+     * in each of the menu items and notifies the listener that the recent file has been selected.
+     *
+     * @param event from a recent file menu item child of this menu.
+     */
+    @Override
+    public void handle(ActionEvent event)
+    {
+        if(mFileSelectionListener != null)
+        {
+            if(event.getSource() instanceof MenuItem)
+            {
+                Object fileObject = ((MenuItem)event.getSource()).getUserData();
+
+                if(fileObject instanceof File)
+                {
+                    mFileSelectionListener.fileSelected((File)fileObject);
+                }
+            }
+        }
+    }
+
+    /**
+     * Listener interface for file selection events.
+     */
+    public interface IFileSelectionListener
+    {
+        void fileSelected(File file);
+    }
+}
diff --git a/src/main/java/io/github/dsheirer/instrument/gui/viewer/RecentFilesMenuItem.java b/src/main/java/io/github/dsheirer/instrument/gui/viewer/RecentFilesMenuItem.java
deleted file mode 100644
index 8efb0899..00000000
--- a/src/main/java/io/github/dsheirer/instrument/gui/viewer/RecentFilesMenuItem.java
+++ /dev/null
@@ -1,106 +0,0 @@
-package io.github.dsheirer.instrument.gui.viewer;
-
-import javafx.event.ActionEvent;
-import javafx.event.EventHandler;
-import javafx.scene.control.Menu;
-import javafx.scene.control.MenuItem;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.io.File;
-import java.util.prefs.Preferences;
-
-public class RecentFilesMenuItem extends Menu implements EventHandler<ActionEvent>
-{
-    private final static Logger mLog = LoggerFactory.getLogger(RecentFilesMenuItem.class);
-
-    private Preferences mPreferences = Preferences.userNodeForPackage(RecentFilesMenuItem.class);
-    private IFileSelectionListener mFileSelectionListener;
-    private String mIdentifier;
-    private int mSize;
-
-    public RecentFilesMenuItem(String identifier, int size)
-    {
-        super("Recent");
-        mIdentifier = identifier;
-        mSize = size;
-
-        load();
-    }
-
-    public void setFileSelectionListener(IFileSelectionListener listener)
-    {
-        mFileSelectionListener = listener;
-    }
-
-    public void add(File file)
-    {
-        if(file != null)
-        {
-            int index = mSize - 1;
-
-            while(index > 0)
-            {
-                String newerItem = mPreferences.get(getKey(index - 1), null);
-
-                if(newerItem != null)
-                {
-                    mPreferences.put(getKey(index), newerItem);
-                }
-
-                index--;
-            }
-
-            mPreferences.put(getKey(0), file.getAbsolutePath());
-        }
-
-        load();
-    }
-
-    private String getKey(int index)
-    {
-        return mIdentifier + ".recent." + index;
-    }
-
-    private void load()
-    {
-        getItems().clear();
-
-        for(int x = 0; x < mSize; x++)
-        {
-            String path = mPreferences.get(getKey(x), null);
-
-            if(path != null)
-            {
-                File file = new File(path);
-
-                if(file.isFile())
-                {
-                    MenuItem menuItem = new MenuItem(file.getName());
-                    menuItem.setUserData(file);
-                    menuItem.setOnAction(this);
-                    getItems().add(menuItem);
-                }
-            }
-        }
-    }
-
-    @Override
-    public void handle(ActionEvent event)
-    {
-        if(mFileSelectionListener != null)
-        {
-            Object fileObject = ((MenuItem)event.getSource()).getUserData();
-
-            if(fileObject instanceof File)
-            {
-                mFileSelectionListener.fileSelected((File)fileObject);
-            }
-        }
-    }
-
-    public interface IFileSelectionListener
-    {
-        void fileSelected(File file);
-    }
-}