http://www.avsforum.com/t/1407589/makemkv-and-lpcm-audio
This post is to share some information and the solution to the problems I was having with MakeMKV and Blu-rays with LPCM audio.
When remuxing Blu-rays containing LPCM audio with MakeMKV, I would not be able to playback the LPCM audio track using anything, including VLC on PC, Popcorn Hour c200, Boxee Box, etc. MakeMKV sets the Codec ID to "A_MS/ACM" which is a very uncommon codec.
- To solve this problem, open MKVmerge GUI, and go to File -> Header Editor.
- Then go to File -> Open and browse to your MKV.
- Scroll down to the audio track that contains the LPCM audio and change the Codec ID from "A_MS/ACM" to "A_PCM/INT/LIT".
- Then File -> Save.
Your MKV will now contain an LPCM audio track that should be compatible with any software or hardware capable of playing MKV files... Hope this helps...