I released this tool a few years back in the minecraft console modding community for extracting and replacing music (*.binka, Bink Audio files ). It should work excellent. Although I haven't checked if its compatible with newer versions of miles sound system, as it was created using sdk of MSS 9. I know there are other tools out there for extraction, but I believe mine is the only one capable of producing a valid binka file from wav.
I have full source for miles sound system 9 and its SDK. If knowledge obtained from that could be useful for anyone give me a hoot. my twitter is @thesilverstoner.
http://www.mediafire.com/file/5xrgeoppu ... n.exe/file