Does anyone have similar problem with Pass Amp?

It is not normal and you should contact Pass Labs. There is obviously a difference in performance between channels in terms of gain and / or noise floor. Sean
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THANKS SEAN, BUT I HAVE CONTACTED PASS LABS AND THEY CLAIM IT'S NORMAL. I DON'T KNOW WHAT TO THINK. I PREVIOUSLY OWNED A CLASSE CA201 AS WELL AS A CLASSE CAP150 INTEGRADED AND THEY BOTH DID THE SAME THING.I'VE EXPERIMENTED WITH SWITCHING AND SWAPPING INTERCONNECTS AND POWER CORDS AS WELL AS ISOLATING ALL CORDS AND USING DIFFERENT OUTLETS. PASS CLAIMS IT'S DUE TO THE TRANSFORMER HAVING WIRES GOING TO IT FROM ONE SIDE ONLY AND THAT THEY COULD ELIMINATE THIS VERY SLIGHT HUM BUT AT THE EXPENSE OF THE SONIC QUALITY OF THE AMP.IT REALLY IS ONLY NOTICABLE IF I'M INCHES FROM THE SPEAKER BUT I DON'T KNOW IF THIS IS NORMAL.

MITCHb, I can inform you that after your thread I give a check to my Pass Aleph (class A single ended amp). Turned it on, and noted exactly what you described. I have both speakers the classic background hiss + a very slight bzzz from right speaker.

The fact that I catch it just after your thread means that it is really very low in intensity.
If this is the case, do not compromise with sound quality and just keep it as it is.
Cheers

That is normal. However, make sure your're system is only grounded through the preamp even if you have to use cheater plugs and new cheater plugs like anything else must be broken in [break in on a high resolution system is about 330hrs.of music not just a idle current flow].

It is probably coming from your wall outlet, and/or nearby equipment (TV/other electronics/PC). Do the tests with switching cables and try to reproduce in the other speaker, then you can trace it back. Also try switching the outlet it is plugged into, as well as cheater plugs.