If everything is disconnected and you hear a hum from this unit, I beleive you may have a transformer hum. (a noisy transformer) In this case, it would be wise to discuss this with the amplifier manufacturer. cordially, Richard..
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-