That you can pesudo have a custom soundtrack? I dicovered this tonight when I was about to hop off 4 for a little break and listen to some music. I got to launch the music and it played in-game! BUT it doesn’t play during matches (at least online anyway, but I assume it doesn’t offline either).
So if you’re tired of hearing “Indestructable” all day, you can have your playlist goinf up intil you enter a lobby/match. WHen you leave a lobby and go back to the main menu/lobby search screens, your playlist will start back up automatically.