diff --git a/Core/HLE/sceMpeg.cpp b/Core/HLE/sceMpeg.cpp
index e62afc50d5..a1df84ff6d 100644
--- a/Core/HLE/sceMpeg.cpp
+++ b/Core/HLE/sceMpeg.cpp
@@ -1019,6 +1019,8 @@ int sceMpegGetAvcAu(u32 mpeg, u32 streamId, u32 auAddr, u32 attrAddr)
 		return -1;
 	}
 
+	ctx->mediaengine->setVideoStream(streamInfo->second.num);
+
 	if (streamInfo->second.needsReset)
 	{
 		sceAu.pts = 0;
@@ -1099,6 +1101,10 @@ int sceMpegGetAtracAu(u32 mpeg, u32 streamId, u32 auAddr, u32 attrAddr)
 		sceAu.pts = 0;
 		streamInfo->second.needsReset = false;
 	}
+	if (streamInfo != ctx->streamMap.end())
+		ctx->mediaengine->setAudioStream(streamInfo->second.num);
+	else
+		WARN_LOG_REPORT(ME, "sceMpegGetAtracAu: invalid audio stream %08x", streamId);
 
 	// The audio can end earlier than the video does.
 	if (mpegRingbuffer.packetsFree == mpegRingbuffer.packets) {
@@ -1245,7 +1251,7 @@ u32 sceMpegAvcCopyYCbCr(u32 mpeg, u32 sourceAddr, u32 YCbCrAddr)
 
 u32 sceMpegAtracDecode(u32 mpeg, u32 auAddr, u32 bufferAddr, int init)
 {
-	DEBUG_LOG(ME, "UNIMPL sceMpegAtracDecode(%08x, %08x, %08x, %i)", mpeg, auAddr, bufferAddr, init);
+	DEBUG_LOG(ME, "sceMpegAtracDecode(%08x, %08x, %08x, %i)", mpeg, auAddr, bufferAddr, init);
 
 	MpegContext *ctx = getMpegCtx(mpeg);
 	if (!ctx) {
diff --git a/Core/HW/MediaEngine.cpp b/Core/HW/MediaEngine.cpp
index d6ce76a8aa..79570d8c8f 100644
--- a/Core/HW/MediaEngine.cpp
+++ b/Core/HW/MediaEngine.cpp
@@ -266,19 +266,9 @@ bool MediaEngine::openContext() {
 			return false;
 	}
 
-	// Get a pointer to the codec context for the video stream
-	m_pCodecCtx = m_pFormatCtx->streams[m_videoStream]->codec;
-
-	// Find the decoder for the video stream
-	AVCodec *pCodec = avcodec_find_decoder(m_pCodecCtx->codec_id);
-	if(pCodec == NULL)
+	if (!setVideoStream(m_videoStream, true))
 		return false;
 
-	// Open codec
-	AVDictionary *optionsDict = 0;
-	if(avcodec_open2(m_pCodecCtx, pCodec, &optionsDict)<0)
-		return false; // Could not open codec
-
 	setVideoDim();
 	m_audioContext = AT3Create();
 	m_isVideoEnd = false;
@@ -341,7 +331,6 @@ int MediaEngine::addStreamData(u8* buffer, int addSize) {
 			size  = 0;
 		if (m_demux) {
 			m_demux->addStreamData(buffer, addSize);
-			m_demux->demux(m_audioStream);
 		}
 #ifdef USE_FFMPEG
 		if (!m_pFormatCtx && m_pdata->getQueueSize() >= 2048) {
@@ -358,6 +347,39 @@ int MediaEngine::addStreamData(u8* buffer, int addSize) {
 	return size;
 }
 
+bool MediaEngine::setVideoStream(int streamNum, bool force) {
+	if (m_videoStream == streamNum && !force) {
+		// Yay, nothing to do.
+		return true;
+	}
+
+	m_videoStream = streamNum;
+#ifdef USE_FFMPEG
+	if (m_pFormatCtx) {
+		if (m_pCodecCtx) {
+			avcodec_close(m_pCodecCtx);
+		}
+
+		// Get a pointer to the codec context for the video stream
+		m_pCodecCtx = m_pFormatCtx->streams[m_videoStream]->codec;
+
+		// Find the decoder for the video stream
+		AVCodec *pCodec = avcodec_find_decoder(m_pCodecCtx->codec_id);
+		if (pCodec == NULL) {
+			return false;
+		}
+
+		// Open codec
+		AVDictionary *optionsDict = 0;
+		if (avcodec_open2(m_pCodecCtx, pCodec, &optionsDict) < 0) {
+			return false; // Could not open codec
+		}
+	}
+#endif
+
+	return true;
+}
+
 bool MediaEngine::setVideoDim(int width, int height)
 {
 #ifdef USE_FFMPEG
@@ -670,6 +692,10 @@ int MediaEngine::getAudioSamples(u32 bufferPtr) {
 	if (!m_demux) {
 		return 0;
 	}
+
+	// Demux now (rather than on add data) so that we select the right stream.
+	m_demux->demux(m_audioStream);
+
 	u8 *audioFrame = 0;
 	int headerCode1, headerCode2;
 	int frameSize = m_demux->getNextaudioFrame(&audioFrame, &headerCode1, &headerCode2);
diff --git a/Core/HW/MediaEngine.h b/Core/HW/MediaEngine.h
index 3969f5901a..4e9c6dc6f2 100644
--- a/Core/HW/MediaEngine.h
+++ b/Core/HW/MediaEngine.h
@@ -65,7 +65,7 @@ public:
 	// Returns number of packets actually added. I guess the buffer might be full.
 	int addStreamData(u8* buffer, int addSize);
 
-	void setVideoStream(int streamNum) { m_videoStream = streamNum; }
+	bool setVideoStream(int streamNum, bool force = false);
 	void setAudioStream(int streamNum) { m_audioStream = streamNum; }
 
 	u8 *getFrameImage();