Likely source of hum (120 hz?) on one channel?

[Downhome Upstate]

With or w/o input applied & regardless of source selected, I've got hum on one channel  significantly louder than the other.  What are the likely culprits?

 

[Grainger49]

Mike,

Did you short the inputs?  120 Hz should be from the power supply.  But it should be both channels if it is the power supply.  Maybe the power supply wires are routed such that they impress noise into the channel you have problems with.

 

[Downhome Upstate]

Thanks, Grainger. Nope, haven't used shorting plugs. I'll try moving the PS wiring around a bit. . .

 

[Paul Joppa]

You didn't mention having adjusted the hum pot - just sayin' ...

 

[Downhome Upstate]

Hi, Paul.  I did (adjust the hum pot, that is).  What I didn't do was pay attention before my first post. It's not the amp. It's the Seduction  :-\