I converted all of my BD's to play on my aTV 3 with AC3 audio tracks. I recently started re-converting for my aTV 3 and iPad 3. I'm converting the multi-channel audio to AAC stereo and AC3 6-channel. Any stereo or mono tracks like commentaries or original audio are keeping their original mix just being converted to AAC. I've spent the last week ripping and converting everything again, naturally, this is taking a long time. All I want is new audio tracks as everything else can stay the same, so I've been looking for a solution to handle converting and extracting audio tracks. I tried MP4Tools last night, but it won't allow me to open any .m4v files. I thought MP4Tools was the MP4 editor and MKVTools was the MKV editor, did I misunderstand something? Any suggestions?