Friedman Runt 20 hum?

[itsme]

Friedman Runt 20 started to hum. Like 60 cycle. Replaced all the tubes, but still there. Any ideas/suggestions?

 

[Waldo Nova]

Did your power source change? I always try plugging into different outlets, powerstrips, turn lights on/off, check the microwave... anything can cause that annoying hum. If you have a pedalboard, a culprit could be the power source being too close to a flanger or something like that. Good luck.

 

[itsme]

Did your power source change? I always try plugging into different outlets, powerstrips, turn lights on/off, check the microwave... anything can cause that annoying hum. If you have a pedalboard, a culprit could be the power source being too close to a flanger or something like that. Good luck.

Nothing changed

 

[RACKSYSTEMS]

With nothing plugged into the loop or the input it hums?

 

[itsme]

With nothing plugged into the loop or the input it hums?

Actually I had asked this question for a friend. He has since talked to Dave and his amp is on the way back to the shop. Apparently there was a bad batch of caps or something in the rungs that need to be fixed