The PlayStation 3 is unable to play music while playing a game, which can be either a PlayStation 3 game or backwards-compatible PlayStation 1 and 2 games. The music-playing feature can be used while performing other tasks, however.
The PlayStation 3's software for playing music is allowed to run while surfing web pages or viewing pictures. Press the PS button on the controller to bring up the PlayStation background while using one of the two applications the system is allowed to run simultaneously. A transparent block will then be placed around the screen to access the music player, which can be returned to by pressing the PS button on the controller again.