diff --git a/src/apps/mediaplayer/media_node_framework/video/VideoProducer.cpp b/src/apps/mediaplayer/media_node_framework/video/VideoProducer.cpp
index e39479f208..96783ab517 100644
--- a/src/apps/mediaplayer/media_node_framework/video/VideoProducer.cpp
+++ b/src/apps/mediaplayer/media_node_framework/video/VideoProducer.cpp
@@ -791,17 +791,12 @@ h->start_time = 0;
 							"playlistFrame: %Ld\n", fFrame, playlistFrame);
 						bool forceOrWasCached = forceSendingBuffer;
 	
-						if (fManager->LockWithTimeout(5000) == B_OK) {
-							// we need to lock the manager, or our
-							// fSupplier might work on bad data
-							err = fSupplier->FillBuffer(playlistFrame,
-								buffer->Data(), &mf, forceOrWasCached);
-							fManager->Unlock();
-						} else {
-							err = B_ERROR;
-						}
+						err = fSupplier->FillBuffer(playlistFrame,
+							buffer->Data(), &mf, forceOrWasCached);
 						// clean the buffer if something went wrong
 						if (err != B_OK) {
+							// TODO: should use "back value" according
+							// to color space!
 							memset(buffer->Data(), 0, h->size_used);
 							err = B_OK;
 						}
diff --git a/src/apps/mediaplayer/supplier/ProxyAudioSupplier.cpp b/src/apps/mediaplayer/supplier/ProxyAudioSupplier.cpp
index 761551a053..5f2c5a9d53 100644
--- a/src/apps/mediaplayer/supplier/ProxyAudioSupplier.cpp
+++ b/src/apps/mediaplayer/supplier/ProxyAudioSupplier.cpp
@@ -43,7 +43,9 @@ struct PlayingInterval {
 
 
 ProxyAudioSupplier::ProxyAudioSupplier(PlaybackManager* playbackManager)
-	: fPlaybackManager(playbackManager)
+	: fSupplierLock("audio supplier lock")
+
+	, fPlaybackManager(playbackManager)
 	, fVideoFrameRate(25.0)
 
 	, fSupplier(NULL)
@@ -98,6 +100,8 @@ ProxyAudioSupplier::GetFrames(void* buffer, int64 frameCount,
 		TRACE("GetFrames() - LOCKING THE PLAYBACK MANAGER TIMED OUT!!!\n");
 	}
 
+	BAutolock _(fSupplierLock);
+
 	// retrieve the audio data for each interval.
 	int64 framesRead = 0;
 	while (!playingIntervals.IsEmpty()) {
@@ -165,6 +169,8 @@ ProxyAudioSupplier::SetFormat(const media_format& format)
 		TRACE("SetFormat(%s)\n", string);
 	#endif
 
+	BAutolock _(fSupplierLock);
+
 	fAudioResampler.SetFormat(format);
 
 	// In case SetSupplier was called before, we need
@@ -199,6 +205,8 @@ ProxyAudioSupplier::SetSupplier(AudioTrackSupplier* supplier,
 //videoFrameRate);
 	TRACE("SetSupplier(%p, %.1f)\n", supplier, videoFrameRate);
 
+	BAutolock _(fSupplierLock);
+
 	fSupplier = supplier;
 	fVideoFrameRate = videoFrameRate;
 
diff --git a/src/apps/mediaplayer/supplier/ProxyAudioSupplier.h b/src/apps/mediaplayer/supplier/ProxyAudioSupplier.h
index e8194cb8d9..b265ff9d35 100644
--- a/src/apps/mediaplayer/supplier/ProxyAudioSupplier.h
+++ b/src/apps/mediaplayer/supplier/ProxyAudioSupplier.h
@@ -5,6 +5,7 @@
 #ifndef PROXY_AUDIO_SUPPLIER_H
 #define PROXY_AUDIO_SUPPLIER_H
 
+#include <Locker.h>
 
 #include "AudioResampler.h"
 #include "AudioSupplier.h"
@@ -45,6 +46,8 @@ private:
 			void*				_SkipFrames(void* buffer, int64 frames) const;
 
 private:
+	BLocker						fSupplierLock;
+
 	PlaybackManager*			fPlaybackManager;
 	float						fVideoFrameRate;
 
diff --git a/src/apps/mediaplayer/supplier/ProxyVideoSupplier.cpp b/src/apps/mediaplayer/supplier/ProxyVideoSupplier.cpp
index 2fd0ce0e9d..a03f9f8c61 100644
--- a/src/apps/mediaplayer/supplier/ProxyVideoSupplier.cpp
+++ b/src/apps/mediaplayer/supplier/ProxyVideoSupplier.cpp
@@ -12,7 +12,8 @@
 
 
 ProxyVideoSupplier::ProxyVideoSupplier()
-	: fSupplier(NULL)
+	: fSupplierLock("video supplier lock")
+	, fSupplier(NULL)
 {
 }
 
@@ -26,6 +27,7 @@ status_t
 ProxyVideoSupplier::FillBuffer(int64 startFrame, void* buffer,
 	const media_format* format, bool& wasCached)
 {
+	BAutolock _(fSupplierLock);
 //printf("ProxyVideoSupplier::FillBuffer(%lld)\n", startFrame);
 	if (fSupplier == NULL)
 		return B_NO_INIT;
@@ -60,6 +62,8 @@ ProxyVideoSupplier::DeleteCaches()
 void
 ProxyVideoSupplier::SetSupplier(VideoTrackSupplier* supplier)
 {
+	BAutolock _(fSupplierLock);
+
 	fSupplier = supplier;
 }
 
diff --git a/src/apps/mediaplayer/supplier/ProxyVideoSupplier.h b/src/apps/mediaplayer/supplier/ProxyVideoSupplier.h
index 505989c387..2bf41f1352 100644
--- a/src/apps/mediaplayer/supplier/ProxyVideoSupplier.h
+++ b/src/apps/mediaplayer/supplier/ProxyVideoSupplier.h
@@ -5,6 +5,7 @@
 #ifndef PROXY_VIDEO_SUPPLIER_H
 #define PROXY_VIDEO_SUPPLIER_H
 
+#include <Locker.h>
 
 #include "VideoSupplier.h"
 
@@ -26,6 +27,8 @@ public:
 			void				SetSupplier(VideoTrackSupplier* supplier);
 
 private:
+			BLocker				fSupplierLock;
+
 			VideoTrackSupplier*	fSupplier;
 };