I was hoping to find some help on a buzz issue I'm having.

My ZRock2 unit produces a buzz (through the speakers, not the unit itself) when the volume is turned up loud.

I have it paired with a UFO amp. When the gain of the ZR2 is at 1pm and the gain of the UFO is at 3pm (no other preamp in the chain), there's an audible buzz that you can clearly hear from 12+ feet away coming through the speakers. If I flick the switch that bypasses the ZR2, the buzz virtually goes away, no matter how high the gain on each device is turned up.

I've swapped power cords, IC cables, repositioned every component on my shelf, moved things further from the electrical outlet, tried different outlets, and the noise persists. I've also swapped the tube and fuse in the ZR2 but nothing seems to help.

The noise happens even when my source is switched off, so I know it's not a problem happening upstream - the issue seems to be specific to the ZR2.

With 95db speakers, my system plays loud enough that I don't really need to crank the UFO volume higher than say, 2pm on the dial, but the buzz is there and I just wish the ZR2 was as quiet as when it was being bypassed.

FWIW, I also just received this unit back from Decware, who repaired wiring that was accidentally swapped (left channel into right, etc). I don't recall having this issue before, but I'm not 100% that it's a new issue.

Any suggestions?

Yeah, both the stock tube that shipped with the ZR2 and a NOS tube. I've used both tubes with no issue over the last couple months and the swapping of tubes doesn't impact the buzz.

I added a Swiss Digital Fuse Box to the UFO but other than that, nothing else has changed. I've tried repositioning the power cables but nothing has an audible effect. Yeah, I have an email in to Steve so we'll see.

Thanks!

Thank you Phill! I sent you an email.