Hello everybody, I am new to this site. I just found it browsing for solutions to my problem.
Currently I am running a Pioneer VSX-D510 Receiver with a powered sub and two KLH floor speakers. Anyways, when the receiver is in standby mode there is no noise emitted like there shouldn't be. When I hit the power button, a humming noise starts right away from the receiver before any sound is even heard from the speakers. This noise continues even after the receiver "clicks on" to produce sound from the speakers. The noise stops when the receiver is turned off. I isolated the receiver in a different room to see if my tv or DVD player or sub is causing the problem. Secondly, I disconnected everything from the receiver, so no speakers were being run. Still made the noise. Any ideas what could be causing this?
I just had a similar problem with mine (Harmon Kardon). Sounds like it's the receiver itself, and not interference since when unplugged from all other items and moved it still occurs. I looked into having mine repaired and turns out to be more of a hassle and not cost effective for anything at about or under $1,000.