diff --git a/reactos/dll/win32/sndblst/sndblst.c b/reactos/dll/win32/sndblst/sndblst.c
index 9eefcd2e1c3..28cc903d808 100644
--- a/reactos/dll/win32/sndblst/sndblst.c
+++ b/reactos/dll/win32/sndblst/sndblst.c
@@ -14,7 +14,7 @@
 
 #include <windows.h>
 #include <ntddsnd.h>
-#include <reactos/sndtypes.h>
+#include <sndtypes.h>
 #include <mmddk.h>
 #include <mmebuddy.h>
 #include <mment4.h>
diff --git a/reactos/include/reactos/libs/sound/mmebuddy.h b/reactos/include/reactos/libs/sound/mmebuddy.h
index b1923886c25..c4b2291c4d8 100644
--- a/reactos/include/reactos/libs/sound/mmebuddy.h
+++ b/reactos/include/reactos/libs/sound/mmebuddy.h
@@ -13,7 +13,8 @@
  *
  * NOTES:       MME Buddy was the best name I could come up with...
  *              The structures etc. here should be treated as internal to the
- *              library so should not be directly accessed elsewhere.
+ *              library so should not be directly accessed elsewhere. Perhaps they
+ *              can be moved to an internal header?
 */
 
 #ifndef ROS_AUDIO_MMEBUDDY_H
diff --git a/reactos/lib/drivers/sound/mmebuddy/thread.c b/reactos/lib/drivers/sound/mmebuddy/thread.c
index 273413f7c5d..3c3aac90683 100644
--- a/reactos/lib/drivers/sound/mmebuddy/thread.c
+++ b/reactos/lib/drivers/sound/mmebuddy/thread.c
@@ -194,7 +194,10 @@ MMRESULT
 DestroySoundThread(
     IN  PSOUND_THREAD Thread)
 {
-    /* TODO: Implement me! */
+    VALIDATE_MMSYS_PARAMETER( Thread );
+    SND_TRACE(L"Terminating sound thread\n");
+    Thread->Running = FALSE;
+    /* TODO: Implement me! Wait for thread to have finished? */
     return MMSYSERR_NOTSUPPORTED;
 }
 
diff --git a/reactos/lib/drivers/sound/mmebuddy/wave/header.c b/reactos/lib/drivers/sound/mmebuddy/wave/header.c
index 7cf01ebb9b6..c5fa5d910d5 100644
--- a/reactos/lib/drivers/sound/mmebuddy/wave/header.c
+++ b/reactos/lib/drivers/sound/mmebuddy/wave/header.c
@@ -155,8 +155,29 @@ EnqueueWaveHeader(
     if ( ! FunctionTable->SubmitWaveHeader )
         return MMSYSERR_NOTSUPPORTED;
 
-    return WaveHeaderOperation(FunctionTable->SubmitWaveHeader,
-                               SoundDeviceInstance,
-                               Header);
-}
+    /*
+        A few minor sanity checks - any custom checks should've been carried
+        out during wave header preparation etc.
+    */
+    VALIDATE_MMSYS_PARAMETER( Header->lpData != NULL );
+    VALIDATE_MMSYS_PARAMETER( Header->dwBufferLength > 0 );
+    VALIDATE_MMSYS_PARAMETER( Header->dwFlags & WHDR_PREPARED );
+    VALIDATE_MMSYS_PARAMETER( ! Header->dwFlags & WHDR_INQUEUE );
 
+    /* Clear the "done" flag for the buffer */
+    Header->dwFlags &= ~WHDR_DONE;
+
+    Result =  WaveHeaderOperation(FunctionTable->SubmitWaveHeader,
+                                  SoundDeviceInstance,
+                                  Header);
+
+    if ( ! MMSUCCESS(Result) )
+    {
+        return Result;
+    }
+
+    /* Set the "in queue" flag if everything was OK */
+    Header->dwFlags |= WHDR_INQUEUE;
+
+    return MMSYSERR_NOERROR;
+}
diff --git a/reactos/lib/drivers/sound/mment4/detect.c b/reactos/lib/drivers/sound/mment4/detect.c
index d76b9d76eb8..06d03411d1d 100644
--- a/reactos/lib/drivers/sound/mment4/detect.c
+++ b/reactos/lib/drivers/sound/mment4/detect.c
@@ -15,8 +15,8 @@
 #include <mmsystem.h>
 #include <mmddk.h>
 #include <ntddsnd.h>
-#include <reactos/sndnames.h>
-#include <reactos/sndtypes.h>
+#include <sndnames.h>
+#include <sndtypes.h>
 
 #include <mmebuddy.h>
 #include <mment4.h>
diff --git a/reactos/lib/drivers/sound/mment4/registry.c b/reactos/lib/drivers/sound/mment4/registry.c
index 482998b8452..a606ef77736 100644
--- a/reactos/lib/drivers/sound/mment4/registry.c
+++ b/reactos/lib/drivers/sound/mment4/registry.c
@@ -13,8 +13,8 @@
 #include <mmddk.h>
 #include <ntddsnd.h>
 
-#include <reactos/sndnames.h>
-#include <reactos/sndtypes.h>
+#include <sndnames.h>
+#include <sndtypes.h>
 
 #include <mmebuddy.h>
 #include <mment4.h>