Looks more to me (and others, according to other recent threads on the subject) like the other way round, the referee waits for the music to fade before blowing the whistle.
For sure that's a good thing. Shouldn't have the referee standing around waiting for the thing to finish though, before he can start the game. Would imagine the League will be having a quiet word about that.
Find it mildly annoying that the kick-off gets delayed for Ring Of Fire, and that it seems to be at the expense of announcing who's on the bench. Bit out of order when it starts actively encroaching on the game you've come to watch. Don't see why it can't just be part of fanzone and then started...