Maril555 is correct in that the hum is audible even if only the amps are connected to the speakers. I disconnected the cable box, the cable modem, and the wireless router, and the hum has diminished to pre-move levels...
Kolledog
Kolledog, you never answered the question, is the hum heard through the speakers or is it a mechanical audible hum from the Amp's power transformers?
If the hum being heard is from the Amps power transformers your problem could be DC offset on the ac power line.
Chances are your audio equipment is now being fed from the same branch circuit as the equipment you mention in your above quote.
When you say you disconnected the cable box, the cable modem, and the wireless router, I assume you unplugged them from the wall power outlet, thus eliminating the problem.
You might try a small isolation transformer to feed the cable box, cable modem, and wireless router from. For a test first you might try using a long drop cord and plugging in these items into another circuit in the house. Maybe for the test a kitchen outlet.