This is both a music player made in Qt and a minecraft mod.
The idea is to handle the music with your own playlists (so while the minecraft sound music should be off, for you to enjoy your music, other game sounds can mix wih the music without problem; ie it doesn't replace your favorite soundpack)
The whole code is free (as 0 cost and as open source) and cross-platform (binaries provided for windows, OS X and GNU/linux)
to see it in action and/or download it, see the video on my website : http://pir2open.net/?load=en_mcmp
This mod which requires ImmersiveEngineering and will make redstone usage conditional
This mod which requires ImmersiveEngineering and will make redstone usage conditional