I'm a complete noob when it comes to converting video/audio on a Mac and I was hoping someone could tell me the easiest way to do the following conversion in Mac OS X; INPUT Mkv container containing - "H.264" HD video stream - "DTS Coherent Acoustics" audio stream OUTPUT Mkv container containing - "H.264" HD video stream (passed through and untouched) - "AC3" audio stream (converted "DTS Coherent Acoustics" audio stream) In Windows one could to this quite easily by using PopCorn MKV AudioConverter. The video stream in the Mkv container and the Mkv container itself would be left untouched and the DTS track would be converted into a AC3 track. And because the video track would be left untouched, converting an entire HD movie would be done in less than 10 minutes (depending on your processor, of course). Is there a similar app for Mac OS X? And if not, what would be the easiest way to do the conversion in Mac OS X? Any help would be greatly appreciated.