Originally Posted By: Matt Finley
Could you please elaborate, what do you mean by 20 kHZ peak? Most of us here haven’t been able to hear that high in over 50 years. How does this limit show itself? Your dog knows, but isn’t saying.
Assuming all your cables are the same as in the other location, are they all shielded?Do mic and speaker cables run parallel to power lines?
Did you get an AC outlet tester to make sure the house is wired correctly (no reversed or floating grounds)?
Is all the audio equipment on one circuit (should be)? Are there other devices like a furnace, microwave, fluorescent lights or refrigerator on that circuit (shouldn’t be)?
Any radio stations or hams nearby?
Where is your router?
Any equipment suffer a beating during the move?
Tons of possibilities. Start disconnecting to try to isolate the problem.

Thanks Matt,
1.the peak and hum are visible on any of a number of EQs graphs within my DAW. MOST folk can't hear 20kHz but what happens up there can be heard by some and can, easily have an impact on audio recording and treatment.
2. All shielded well enough...no parallels.
No outlet tester but do have the power conditioner which would rectify the supply to some degree. I will look into a tester though. On that line the ground loop switch on one of my pedals make the problem worse.
Tested in other rooms down & upstairs and no change so not a single circuit thing. No appliances on the circuit.
Radio station - nope semi rural location - there is a mountain though I don't have a ham radio so wouldn't really be able to tell about other ham radio users.
The machine is offline and the router in the opposite corner of the house AND upstairs. The entire downstairs is brick built walls interior and exterior as well.
Nope no damage, new interface has same problem.
Everything has been isolated, swapped. moved and tested in various modes - including with my hand on them.
Yes tons of possibilities many of which I've addressed and the reason I asked...thanks.


Cheers
rayc
"What's so funny about peace, love & understanding?" - N.Lowe