diff --git a/amalgamation/juce_amalgamated_template.cpp b/amalgamation/juce_amalgamated_template.cpp
index eba370eeba..f103d4da4b 100644
--- a/amalgamation/juce_amalgamated_template.cpp
+++ b/amalgamation/juce_amalgamated_template.cpp
@@ -59,6 +59,10 @@
  #undef JUCE_BUILD_GUI
 #endif
 
+#ifndef JUCE_NAMESPACE
+ #define JUCE_NAMESPACE juce
+#endif
+
 //==============================================================================
 #if JUCE_BUILD_NATIVE || JUCE_BUILD_CORE || (JUCE_BUILD_MISC && (JUCE_PLUGINHOST_VST || JUCE_PLUGINHOST_AU))
  #if JUCE_WINDOWS
diff --git a/juce_Config.h b/juce_Config.h
index e1019141f5..771d55fc86 100644
--- a/juce_Config.h
+++ b/juce_Config.h
@@ -31,14 +31,6 @@
     This file contains macros that enable/disable various JUCE features.
 */
 
-//=============================================================================
-/** The name of the namespace that all Juce classes and functions will be
-    put inside. If this is not defined, no namespace will be used.
-*/
-#ifndef JUCE_NAMESPACE
-  #define JUCE_NAMESPACE juce
-#endif
-
 //=============================================================================
 /** JUCE_FORCE_DEBUG: Normally, JUCE_DEBUG is set to 1 or 0 based on compiler and
     project settings, but if you define this value, you can override this to force
diff --git a/juce_amalgamated.cpp b/juce_amalgamated.cpp
index cc0beb8ef7..ed66f7cd1c 100644
--- a/juce_amalgamated.cpp
+++ b/juce_amalgamated.cpp
@@ -206,13 +206,6 @@
 	This file contains macros that enable/disable various JUCE features.
 */
 
-/** The name of the namespace that all Juce classes and functions will be
-	put inside. If this is not defined, no namespace will be used.
-*/
-#ifndef JUCE_NAMESPACE
-  #define JUCE_NAMESPACE juce
-#endif
-
 /** JUCE_FORCE_DEBUG: Normally, JUCE_DEBUG is set to 1 or 0 based on compiler and
 	project settings, but if you define this value, you can override this to force
 	it to be true or false.
@@ -507,6 +500,10 @@
  #undef JUCE_BUILD_GUI
 #endif
 
+#ifndef JUCE_NAMESPACE
+ #define JUCE_NAMESPACE juce
+#endif
+
 //==============================================================================
 #if JUCE_BUILD_NATIVE || JUCE_BUILD_CORE || (JUCE_BUILD_MISC && (JUCE_PLUGINHOST_VST || JUCE_PLUGINHOST_AU))
  #if JUCE_WINDOWS
@@ -17396,7 +17393,7 @@ void Thread::signalThreadShouldExit()
 bool Thread::waitForThreadToExit (const int timeOutMilliseconds) const
 {
 	// Doh! So how exactly do you expect this thread to wait for itself to stop??
-	jassert (getThreadId() != getCurrentThreadId());
+	jassert (getThreadId() != getCurrentThreadId() || getCurrentThreadId() == 0);
 
 	const int sleepMsPerIteration = 5;
 	int count = timeOutMilliseconds / sleepMsPerIteration;
@@ -247258,7 +247255,7 @@ void MessageManager::doPlatformSpecificShutdown()
 	OleUninitialize();
 }
 
-class DeviceChangeDetector   // (Used by various audio classes)
+class DeviceChangeDetector  : private Timer // (Used by various audio classes)
 {
 public:
 	DeviceChangeDetector (const wchar_t* const name)
@@ -247283,11 +247280,18 @@ private:
 				  || wParam == 0x8004 /*DBT_DEVICEREMOVECOMPLETE*/
 				  || wParam == 0x0007 /*DBT_DEVNODES_CHANGED*/))
 		{
-			((DeviceChangeDetector*) GetWindowLongPtr (h, GWLP_USERDATA))->systemDeviceChanged();
+			// We'll pause before sending a message, because on device removal, the OS hasn't always updated
+			// its device lists correctly at this point. This also helps avoid repeated callbacks.
+			((DeviceChangeDetector*) GetWindowLongPtr (h, GWLP_USERDATA))->startTimer (500);
 		}
 
 		return DefWindowProc (h, message, wParam, lParam);
 	}
+
+	void timerCallback()
+	{
+		systemDeviceChanged();
+	}
 };
 
 #endif
@@ -256396,7 +256400,7 @@ public:
 
 	void handleSysEx (MIDIHDR* const hdr, const uint32 timeStamp)
 	{
-		if (isStarted)
+		if (isStarted && hdr->dwBytesRecorded > 0)
 		{
 			concatenator.pushMidiData (hdr->lpData, hdr->dwBytesRecorded, convertTimeStamp (timeStamp), input, callback);
 			writeFinishedBlocks();
diff --git a/juce_amalgamated.h b/juce_amalgamated.h
index 036aa20c23..95edfabbcd 100644
--- a/juce_amalgamated.h
+++ b/juce_amalgamated.h
@@ -73,7 +73,7 @@ namespace JuceDummyNamespace {}
 */
 #define JUCE_MAJOR_VERSION	  1
 #define JUCE_MINOR_VERSION	  54
-#define JUCE_BUILDNUMBER	3
+#define JUCE_BUILDNUMBER	4
 
 /** Current Juce version number.
 
@@ -254,13 +254,6 @@ namespace JuceDummyNamespace {}
 	This file contains macros that enable/disable various JUCE features.
 */
 
-/** The name of the namespace that all Juce classes and functions will be
-	put inside. If this is not defined, no namespace will be used.
-*/
-#ifndef JUCE_NAMESPACE
-  #define JUCE_NAMESPACE juce
-#endif
-
 /** JUCE_FORCE_DEBUG: Normally, JUCE_DEBUG is set to 1 or 0 based on compiler and
 	project settings, but if you define this value, you can override this to force
 	it to be true or false.
@@ -535,14 +528,13 @@ namespace JuceDummyNamespace {}
 
 /*** End of inlined file: juce_Config.h ***/
 
-#ifdef JUCE_NAMESPACE
-  #define BEGIN_JUCE_NAMESPACE	namespace JUCE_NAMESPACE {
-  #define END_JUCE_NAMESPACE	  }
-#else
-  #define BEGIN_JUCE_NAMESPACE
-  #define END_JUCE_NAMESPACE
+#ifndef JUCE_NAMESPACE
+ #define JUCE_NAMESPACE juce
 #endif
 
+#define BEGIN_JUCE_NAMESPACE	namespace JUCE_NAMESPACE {
+#define END_JUCE_NAMESPACE	  }
+
 
 /*** Start of inlined file: juce_PlatformDefs.h ***/
 #ifndef __JUCE_PLATFORMDEFS_JUCEHEADER__
diff --git a/src/core/juce_StandardHeader.h b/src/core/juce_StandardHeader.h
index 98fc43586b..9b90ee1874 100644
--- a/src/core/juce_StandardHeader.h
+++ b/src/core/juce_StandardHeader.h
@@ -33,7 +33,7 @@
 */
 #define JUCE_MAJOR_VERSION      1
 #define JUCE_MINOR_VERSION      54
-#define JUCE_BUILDNUMBER        3
+#define JUCE_BUILDNUMBER        4
 
 /** Current Juce version number.
 
@@ -52,14 +52,13 @@
 #include "../../juce_Config.h"
 
 //==============================================================================
-#ifdef JUCE_NAMESPACE
-  #define BEGIN_JUCE_NAMESPACE    namespace JUCE_NAMESPACE {
-  #define END_JUCE_NAMESPACE      }
-#else
-  #define BEGIN_JUCE_NAMESPACE
-  #define END_JUCE_NAMESPACE
+#ifndef JUCE_NAMESPACE
+ #define JUCE_NAMESPACE juce
 #endif
 
+#define BEGIN_JUCE_NAMESPACE    namespace JUCE_NAMESPACE {
+#define END_JUCE_NAMESPACE      }
+
 //==============================================================================
 #include "juce_PlatformDefs.h"
 
diff --git a/src/native/windows/juce_win32_Messaging.cpp b/src/native/windows/juce_win32_Messaging.cpp
index 5b237f40de..e933252902 100644
--- a/src/native/windows/juce_win32_Messaging.cpp
+++ b/src/native/windows/juce_win32_Messaging.cpp
@@ -345,7 +345,7 @@ void MessageManager::doPlatformSpecificShutdown()
 }
 
 //==============================================================================
-class DeviceChangeDetector   // (Used by various audio classes)
+class DeviceChangeDetector  : private Timer // (Used by various audio classes)
 {
 public:
     DeviceChangeDetector (const wchar_t* const name)
@@ -370,11 +370,18 @@ private:
                   || wParam == 0x8004 /*DBT_DEVICEREMOVECOMPLETE*/
                   || wParam == 0x0007 /*DBT_DEVNODES_CHANGED*/))
         {
-            ((DeviceChangeDetector*) GetWindowLongPtr (h, GWLP_USERDATA))->systemDeviceChanged();
+            // We'll pause before sending a message, because on device removal, the OS hasn't always updated
+            // its device lists correctly at this point. This also helps avoid repeated callbacks.
+            ((DeviceChangeDetector*) GetWindowLongPtr (h, GWLP_USERDATA))->startTimer (500);
         }
 
         return DefWindowProc (h, message, wParam, lParam);
     }
+
+    void timerCallback()
+    {
+        systemDeviceChanged();
+    }
 };
 
 #endif
diff --git a/src/native/windows/juce_win32_Midi.cpp b/src/native/windows/juce_win32_Midi.cpp
index 3e2376ede6..4ac908b038 100644
--- a/src/native/windows/juce_win32_Midi.cpp
+++ b/src/native/windows/juce_win32_Midi.cpp
@@ -73,7 +73,7 @@ public:
 
     void handleSysEx (MIDIHDR* const hdr, const uint32 timeStamp)
     {
-        if (isStarted)
+        if (isStarted && hdr->dwBytesRecorded > 0)
         {
             concatenator.pushMidiData (hdr->lpData, hdr->dwBytesRecorded, convertTimeStamp (timeStamp), input, callback);
             writeFinishedBlocks();
diff --git a/src/threads/juce_Thread.cpp b/src/threads/juce_Thread.cpp
index cb44891a3c..69e5e75764 100644
--- a/src/threads/juce_Thread.cpp
+++ b/src/threads/juce_Thread.cpp
@@ -225,7 +225,7 @@ void Thread::signalThreadShouldExit()
 bool Thread::waitForThreadToExit (const int timeOutMilliseconds) const
 {
     // Doh! So how exactly do you expect this thread to wait for itself to stop??
-    jassert (getThreadId() != getCurrentThreadId());
+    jassert (getThreadId() != getCurrentThreadId() || getCurrentThreadId() == 0);
 
     const int sleepMsPerIteration = 5;
     int count = timeOutMilliseconds / sleepMsPerIteration;