I thought it was already synced?
only thing i can think of is playing it client sided (no bricks involved) and having it start for all of the players at oncehttp://rtb-archive.host22.com/add_ons/Event_MinigameMusic.zipthat might be something to go off of ^
You can possibly split up a music file into segments and play them in order with events.Every time the event is triggered it syncs back up with all players in range
what about at the end of a loop, it "plays" it again using relays (basically the same thing as opening the menu, clicking the music, and pressing "send")that way if a player joins, they will sync up next time the loop loops