Help me solve another speaker hum thread :)

@noromance to clarify, the speaker still hums when ONLY the MC901 is powered and connected to speaker via speaker cables. No other cables or devices are connected, powered, or even plugged into an outlet. Nothing else is on the circuit.

I checked cable routing, nothing is touching. I tried 2 other dedicated outlets, no effect. I reseated tubes, no effect. I even swapped all tubes with the other MC901, no effect. I swapped power cords, no effect. I disconnected and reconnected speaker cables, no effect. Did not try swapping speaker cables with other speaker, maybe will try tomorrow.

At this point I think there is something wrong with the amp. It weighs 180 lbs though, too heavy to move by myself to the other speaker to see if the issue will replicate.

Guess I’ll contact my dealer.

Just to be clear, this is definitely an issue that needs to be corrected (i.e. a serious issue?)? Or will my dealer shrug and think I’m being a "picky customer"? I don’t know how big of a dealer speaker hum caused by amp is. 

And should I have my dealer address both amps? Even the one that has a barely audible hum with my ear less than an inch away? Or just the louder one that I can hear hum from 6 inches away? Thoughts?

Thanks all

Ya I’m sure the tubes are correct. I tried swapping all the tubes out with the other amp but that did not effect anything. No wifi or AP’s. I do live about 0.2 miles from 3 AM radio towers and 1 FM radio tower... could that be causing issues? I wouldn’t think so?

I spoke to my dealer today, they are gonna come take a look. I'll update the thread when they do. In the meantime if anyone has any great ideas, feel free to share :)