Niles ZR 4630 Multi Zone Amplifier Controller Receiver ZR4630 AS-IS

This unit is powering up, but I can't make it to produce sound. I don't have the remote, and I don't know how to operate this thing. So it's possible that it's just user error, but I am going to assume that it's not working and am pricing it accordingly. Sold AS-IS for parts / repair only.

Again, it does power up... I can access the radio stations etc. Just no sound.