Amp buzz in speakers


I have an Aragon 4004 MkII amp, brand new Yamaha Aventage RX-A1040 receiver, with B&W 802 Series 2 speakers. I recently installed the system in a new rack system and am pretty sure there is very subtle yet audible hum/buzz coming from both speakers. It doesn't sound like a ground loop as the noise is coming from the mids and tweets as well as the woofers. I'm only mentioning these components as I believe I have narrowed it down.

With only the amp turned on(same with receiver turned on), the sound exists. Volume adjustments have no effect on it. Turning off the receiver has no effect. If I unplug the input cables to the amp, the sound goes away completely. If I unplug only 1 input cable, that channels sound goes away. I've tried different interconnects and all product the same buzz/humm. I've checked for nearby power cables, wall worts, etc, but nothing is close to them. I've also unplugged each of the other source components with no difference.

If anyone has any recommendations, I'm all ears!!

Thanks,

d
dastro
Try using non polarized cheater (get it at Home Depot for less than a dollar)...turn the plug 180 degrees to see if the noise goes away...if so, change the plug wiring...don't use the cheater they lessen the quality of sound...you're just trying to see if its a grounding issue.
I have the amp connected to the receiver via the preamp outputs. But the buzz/hum still exists/doesn't change whatsoever when I disconnect the amp from the receiver.
I just tried an adapter without a grounding plug on it. The hum/buzz was much less noticeable. With it, there was no noise coming from the mids and tweets, only from the woofers. There is still a low level hum, but much better. This was done with a polarized adapter. Should I change out the outlet?

Thanks.
Don't change the outlet. Flip the interconnects to the amp around the opposite way and see if the hum lessens.
Just flipped the interconnects, no changed. As mentioned, noise exists even when interconnects are disconnected from receiver's preamp outs.