Meanwhile, I ported over the deadbeef music player to RetroPie. It has a GTK interface and runs in X. It will play all your music but the special thing about this player is that it can play all sorts of classic chiptune modules as well as actual game music rips from tons of different consoles. It uses actual rips of the music instructions and emulates the console’s sound chips so they sound dead on as well as being far smaller than mp3s. Entire soundtrack for a NES game: 25k, for instance.