I recieved a Bandit 65 from Guitar Center today. Apparently they don't bother to function test used gear before they list it. Listing said "GREAT" condition, but it was not in operating condition when it arrived. Being in really nice physical condition I thought I'd try to clean up the pots and jacks to see if that fixed it before returning it. That took care of everything except for the reverb. When I try turning the reverb up, there's no reverb and it turns the volume down, cutting out all sound by the time it's full up. When turning it back down I get a loud hum as it sweeps from about 3-2. I would appreciate any help y'all can provide trouble shooting the problem. Thanks in advance for your help.