You can already change the music in-game. Just add custom tracks to a music folder in base and then ingame type /music music/<track> (/music music/<folder>/<track> if you wanna put them in categories) into the console, just make sure the tracks are stereo ad 44100 khz in the event that a track name is more than one word, replace all spaces with the underscore '_' character example protectors_of_the_earth. As so /music music/protectors_of_the_earth. They also have to be mp3's. No need for huge mods to enable something already available, good thinking though Enjoy.