power conditioner

@lostbears okay, I read ya. Curious though because in any case fluorescent lighting can be a cause of DC on the line, and in particular if there are any dimmers involved. Also, it doesn't necessarily matter that any "offending DC item" be on the same breaker. DC and anything connected to the same panel is enough to permeate through your entire house. But if as you say you've isolated the issue to the Furman because you didn't have the problem with the Adcom, question then is does the Adcom provide DC filtering? You probably want to do something about the fluorescent lighting in any case. 

 gdhal, I don't know. I sold both the Adcom and Furman after I bought the Shunyata Triton. I also don't actually know how the Triton would fair in the situation. I threw away the light bulb when I found that was the problem. I did not want in the house after that. It seemed to be just one bulb out of the 4 in the fixture.

 I don't have any dimmers. And I have went out of my way to get rid of all compact fluorescent in the house. I also find it interesting that the preamp seems to be the only thing that was affected. There was no buzz in the kitchen radio right next to the dining room. The stereo is on the other side of the house from the dining room.

 But it actually turned out to be some what of a blessing in disguise. If the whole thing had not happened I would still have the Furman. The  Shunyata Triton has a much bigger positive impact on the sound. I am very glad I upgraded and it was a great excuse for the wife. Also it didn't cost me anything to get my Ref 5se checked out by ARC as it was still under warranty. Plus ARC said they did a few updates to it while it was there. My ARC dealer was really nice about it even when they did not find a problem. It was just really annoying at the time.  

For those that can't sleep at night without a surge protector:

https://www.audiogon.com/listings/ac-conditioners-audience-ar2p-high-resolution-power-conditioner-20...

No affiliation.

Best to all,
Dave

I have the Synergistic Research PowerCell 10SE with a 32-amp Powercon connector power cord. this was about the 3rd or 4th generation of the series and what I can tell you is this, space is blacker, no noise whatsoever, dead quite period. I hear details in music I never heard before with a smooth 3D dimensionality landscape. Synergistic Products are expensive.... they are an important part of ones system, but you have to get the good ones, not all are created equal.

^Yep.