Thanks Johann, I did switch around tubes in both the pre-amp and amp and hiss continued in the right channel.
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I tried this morning to pull the circuit boards behind the tubes and they would not budge. I didn’t apply to much pressure but I think I have the soldered kind. I also connected the Blue Sound streamer directly into the amp. At first still had some quieter hiss but after a bit of cable adjustment the hiss was gone. So…tell me what this means, problem is preamp but not tube related?
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Yup that would me my diagnostic finding.
preamp issue.
Did you use the same cables from the node to the amp? If so, and some cable fiddling got rid of the hiss it could be a cable issue.
Thanks club_pizzazz, I think I just didn’t have it seated firmly but just to be sure I swapped out the interconnect cables and the hiss is still there.
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I contacted PS help desk and they are thinking its the tubes. They said hiss does not always swap channels when a tubes are moved from left to right channel because of shared circuitry. Ordering new tubes tomorrow and I’ll keep you posted. Thanks to all who responded.
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Hate to be a pessimist but i got $5.00 that says that does not fix it 
This may or may not apply to you, but I just encountered the exact same symptoms as you describe.
I had just moved my Mac mini (music server) nearer to my BHK Signature Preamp in a re-arrangement scheme. Immediately I noticed a hissing/rhythmic tick in my right speaker.
I moved the Mac mini back to its original position some distance away from the preamp.
No more noise!
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Thanks tmmuchcox, Interesting. I don’t think it applies to me as I have not moved any components around recently and I disconnected and unplugged all adjacent components during my hiss investigation.
I have now replaced the 12AU7 tubes with new ones and, unfortunately the right channel static continues. I have asked PS Audio techs what to do next.
Try removing each source–Node, CD player one at a time.
Thanks RonP, As the thread indicates I have done all of that. It really seems like a non-tube pre-amp issue.
I had exactly the same issue and the culprit was the board behind the tube. As already said by @Baldy swapping the right left boards can give the proof. If your unit still sports the soldered boards it’s not doable, unfortunately. It’s pretty odd because also my unit was 2-3 years old (but I’m based in EU, if that makes some difference).
I received a new board and the issue was instantly fixed.
I’m afraid you need to call again PSA customer service.
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Thanks luca.pelliccioli. I am working with the PA Audio techs. I tried to remove the boards behind the tubes but it appears I have the soldered kind.
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“PS Audio techs”
I wanted to make a final post and wrap this thread up. At PS Audio’s suggestion I sent my pre-amp in to PS Audio for service. They turned it around pretty quickly and the unit is now static free and sounding great. Here is what they said they did:
“Replaced 3.6K ohm resisters on both opto boards. Replaced optos on the right channel. Added capacitor on the bottom of C137.”
Thanks to all who left messages and advice for getting the problem fixed!
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