Posting this here just in case others find it helpful.

For several months, I've been struggling with identifying the source of a faint buzz coming from my speaker drivers, even when everything was powered off. I've tried swapping cables, lifting the ground with a cheater plug, and various products like the Snubway, to no avail.

I recently added a pair of Omega Deep Hemp subwoofers to my system which made the buzz even louder and harder to ignore. After combing through various forums for answers, chatting with Louis from Omega, and emailing Steve, I was finally able to identify the issue and eliminate the buzz.

May seem obvious to some, but it was a ground loop causing the buzz.

Here was my fix:

• I connected a wire between the two negative speaker jacks on my UFO amplifier.  Then, I connected one of those to a ground screw on the amplifier chassis.  This reduced the buzz by about 70%.
• Next I connected a ground wire from the amp plate on my subwoofer to the negative (black) speaker terminal on my loud speakers. I did this for both Left and Right speaker/subs. This reduced the remaining buzz completely.

Now, my system is quiet as a mouse.

Yes. Using another wire, I attached one end to one of the negative speaker posts, and the other end to a screw on the transformer. It's pretty discreet.