The sound may also have some bits embedded. We suspect that the stego bits rate is 120 bpm. Could you extract what’s inside?

https://s3.amazonaws.com/volgactf/stegasic/500/stego.wav

HINT: The solution to the task is in the paper "Techniques for Data Hiding" by W. Bender. You can find it in the archive you retrieved (didn't you) solving stegasic 200.