In the beta version of Hee 1.5 for minecraft 1.7.2, the music was working. When I updated to the official release, it never played music again. This is why I don't think this is a minecraft 1.7.2 bug. I really miss the epic music that used to be played.

Music is disabled in 1.7.2, due to a vanilla bug which caused multiple music tracks to be played at one moment. It will be restored in 1.7.3/newer.