Pass Labs XP-17 right channel hum

The PX-17 sounds great but I have a right chanel hum when the volume control is above 12 0'clock.
In my system I have a Linn Sondek LP12 Klimax, self made tube amps (PP 2a3, SE 845) and preamps, Naim Nap 250 whith his preamp,, Audio Research Reference 3,, Nagra bps phono, Avantgarde Duo Grosso speakers and much other collective stuff.
My system is dead quiet.
The Pass Labs XP-17 has a right chanel hum due to electro magnetic field radiation of the power transformer.
I have rotated the transformer a quarter turn clockwise and solved 90 per cent of the problem, but replacing the top cover on the hum is back but not so bad as before.
I think this is due to a faulty power transformer, I have sent a mail to Pass Labs for help.
Any suggestions or advice?
Thank you
 
There is no doubt because rotating the trasformer the hum is greatly reduced.
There must be a great radiating lobe from the toroid that is not normal.
Maybe the electro magnetic field radiation can be reduced with a trafo shielding sheet from Don Audio.
Any experience with shielding sheets?
 
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I'm getting all my Donuts from local winder (asked, they're not willing to send abroad), with exact specs as said for PL - static shield, magnetic shield

more or less, that's standard for low and line level signal stages, whatever construction in case

I know that magnetic shield on mine is made of same magnetic strip (several turns) as used for xformer toroid core

Anyhow - I don't know what happened with your exact xformer to start spraying bad vibes, so I can't predict how much of that spray could be suppressed using any type of shielding

instead of applying any sort of cure, best to simply replace it with proper quality one - either gotten directly from PL (whatever you agree with them) or ordering locally, by data given by PL

in general, whatever type of shielding, count that thickness of shield is very/most important; so - chunky it must be; even piece of steel tube with thick wall will do the job, nicely wrapped with fabric Tesa tape
 
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I hooked up an older XP17 set at 60dB to a headphone amp via RCA cables. With the volume set to max level, I did not hear any hum on either channel on the headphones.
(Obviously I wasn't playing a record when I did that. :) )

On the odd occasions I contacted PL's service dept via email their responses were very quick, so I imagine you will hear back from them after the weekend.

I hope you have this hum issue resolved soon.