I would need to look at the configuration of the power supply to see if that could be the problem in one channel only; it is not likely.

I would use an oscilloscope to trace through the bad channel and see at what point in the circuit it starts. I would be looking for a bad capacitor or a bad solder joint in the signal path. It could also be a bad op-amp or transistor.

If you are not an experienced techncian, you need to find one and get him to work on it.

bradscrst1 wrote:

I own a Parasound A23 amp that since I have owned it has a buzz and hum in the left speaker, barely audible in the right.I have checked everything I can think of to find the problem.I have disconnected everything except the speakers and power cord and when its on and volume at 0 the buzz and hum persist, I can hear it from approx.2 feet away . right speaker has buzz and hum also but barely audible from 6 inches.Any opinions?