diff --git a/softhddev.c b/softhddev.c
index 102be69..fd51917 100644
--- a/softhddev.c
+++ b/softhddev.c
@@ -1518,6 +1518,11 @@ static void FixPacketForFFMpeg(VideoDecoder * vdecoder, AVPacket * avpkt)
 */
 int VideoPollInput(VideoStream * stream)
 {
+    if (!stream->Decoder) {		// closing
+	fprintf(stderr, "no decoder\n");
+	return -1;
+    }
+
     if (stream->ClearBuffers) {
 	atomic_set(&stream->PacketsFilled, 0);
 	stream->PacketRead = stream->PacketWrite;
@@ -1549,6 +1554,11 @@ int VideoDecodeInput(VideoStream * stream)
     AVPacket *avpkt;
     int saved_size;
 
+    if (!stream->Decoder) {		// closing
+	fprintf(stderr, "no decoder\n");
+	return -1;
+    }
+
     if (stream->ClearBuffers) {		// clear buffer request
 	atomic_set(&stream->PacketsFilled, 0);
 	stream->PacketRead = stream->PacketWrite;
@@ -2987,16 +2997,17 @@ void PipStop(void)
 	return;
     }
 
+    if (PipVideoStream->HwDecoder) {
+	VideoDelHwDecoder(PipVideoStream->HwDecoder);
+	PipVideoStream->HwDecoder = NULL;
+	// FIXME: does CodecVideoClose call hw decoder?
+    }
     if (PipVideoStream->Decoder) {
 	PipVideoStream->SkipStream = 1;
 	CodecVideoClose(PipVideoStream->Decoder);
 	CodecVideoDelDecoder(PipVideoStream->Decoder);
 	PipVideoStream->Decoder = NULL;
     }
-    if (PipVideoStream->HwDecoder) {
-	VideoDelHwDecoder(PipVideoStream->HwDecoder);
-	PipVideoStream->HwDecoder = NULL;
-    }
     VideoPacketExit(PipVideoStream);
 
     PipVideoStream->NewStream = 1;
diff --git a/video.c b/video.c
index 463f9a0..b4d2593 100644
--- a/video.c
+++ b/video.c
@@ -8231,6 +8231,7 @@ static void VdpauSyncRenderFrame(VdpauDecoder * decoder,
     while (atomic_read(&decoder->SurfacesFilled) >= VIDEO_SURFACES_MAX) {
 	struct timespec abstime;
 
+	fprintf(stderr, "video/vdpau: must be removed\n");
 	pthread_mutex_unlock(&VideoLockMutex);
 
 	abstime = decoder->FrameTime;
@@ -8378,6 +8379,7 @@ static void VdpauDisplayHandlerThread(void)
     }
 
     decoded = 0;
+    pthread_mutex_lock(&VideoLockMutex);
     for (i = 0; i < VdpauDecoderN; ++i) {
 	int filled;
 
@@ -8389,10 +8391,8 @@ static void VdpauDisplayHandlerThread(void)
 	filled = atomic_read(&decoder->SurfacesFilled);
 	if (filled < VIDEO_SURFACES_MAX) {
 	    // FIXME: hot polling
-	    pthread_mutex_lock(&VideoLockMutex);
 	    // fetch+decode or reopen
 	    err = VideoDecodeInput(decoder->Stream);
-	    pthread_mutex_unlock(&VideoLockMutex);
 	} else {
 	    err = VideoPollInput(decoder->Stream);
 	}
@@ -8409,6 +8409,7 @@ static void VdpauDisplayHandlerThread(void)
 	}
 	decoded = 1;
     }
+    pthread_mutex_unlock(&VideoLockMutex);
 
     if (!decoded) {			// nothing decoded, sleep
 	// FIXME: sleep on wakeup
@@ -9459,7 +9460,13 @@ struct _video_hw_decoder_
 ///
 VideoHwDecoder *VideoNewHwDecoder(VideoStream * stream)
 {
-    return VideoUsedModule->NewHwDecoder(stream);
+    VideoHwDecoder *hw;
+
+    VideoThreadLock();
+    hw = VideoUsedModule->NewHwDecoder(stream);
+    VideoThreadUnlock();
+
+    return hw;
 }
 
 ///
@@ -9470,7 +9477,9 @@ VideoHwDecoder *VideoNewHwDecoder(VideoStream * stream)
 void VideoDelHwDecoder(VideoHwDecoder * hw_decoder)
 {
     if (hw_decoder) {
+	VideoThreadLock();
 	VideoUsedModule->DelHwDecoder(hw_decoder);
+	VideoThreadUnlock();
     }
 }