Hum on Tube Amp - Can't find source


I have a hum (60hz) I can hear on my speakers and it happens with my tube monoblocks (either of them).  With or without interconnects, it even happens on either amp (have tried one at a time) with every circuit on the house tripped/disconnected, every other component disconnected from the wall (including the Internet/CaTV line) and no interconnects.  

One amp has it as soon as it warms up whereas the other one is intermittent.

Hum X doesn't solve it, iFi Ground defender either, AVA HumDinger on powerline  doesn't solve it either.

I have replaced the tubes and both amps were just tested at the factory.  Replaced the circuit breaker, tightened every wire on the breaker box, checked and cleaned all connections to ground rod.  Added a hum eliminator to the internet line.

Hum cycles a bit with the tube glow matching the cycles.

I'm waiting on the power company to come check the power coming to the house.

Thoughts?

ervikingo

Well I had problems with hum on mine,, Try using an extension cord and plugging them in on other circuts

Post removed 

The substitution of the the 12at7 or Whatever might have something to do with it.

@hiend2 

Try using an extension cord and plugging them in on other circuits

ervikingo has tried that already.

I has a trouble in my preamp similarit was exposed to a Large Magnetic field.

Take the amp to your office,

Try a solid state unit...