A short cut

Bob and Joe are walking home late one night and they pass a graveyard. Bob suggests taking a short cut through it but the Joe has to meet someone elsewhere so they part company.

The next day they meet up.
“You made it through the graveyard then?” says Joe
“Yeah, but you’re right there’s something creepy going on in there.”, says Bob.
“Like what?”, asks Joe
“Well, I could hear this really strange sound, like music being played backwards.”
“Really?”, says Joe, “Tell you what, why don’t I get my tape recorder and we’ll cut through there tonight, see if we can record it?”

The next day they meet up again and Joe plays the tape.
“That sounds classical” say Bob.
“Yeah, it’s Beethoven’s 9th symphony – I’m playing the tape backwards.” says Joe, “And I found out where it’s coming from, come and see.” Joe leads Bob back to the graveyard and up to a grave marked 'Ludwig van Beethoven'.
“I don’t get it,”, says Bob, “Why is the music coming out backwards?”
“It’s obvious really”, says Joe, “He’s decomposing.”