A user of a game system can replace background music from a game with the user's selected background music, while still hearing any other audio streams (e.g. sound effects related to gameplay). A music engine and system audio mixer allow the playback of the user's requested replacement music. The game tags background music streams with an identifier indicating that they are background music, and such streams are muted at the music engine and system audio mixer (if the game is using the provided music engine in order to play the game's audio streams) or by the game if the game is using a game music engine and has received information indicating that a mute request has been issued.