Sean has a good idea. My Adcom hums and I talked to a dealer about it. He told me to open it up and make sure the transformer was tightend down good. I have never bothered doing it beacuse I can't hear it from my listening position. Yes, be careful to make sure you unplug the unit and leave it sitting for a good long while so that the caps discharge. I would let it sit overnight. I'm extra cautious.
Amp Hum
I've got a B&K AV5000 Series II amp with a hum. It gradually builds up over about a 5 second period on startup. I've disconnected everything (preamp, speaker cables) and still the hum persists. I tried a different power cord (Shunyata Sidewinder), made sure everything else was off, tried a cheater plug, different wall socket... still have the hum. I tried the Monidal Magic thing for the cable, still the hum torments me. Is it time to take it in or am I missing something? Thanks-