Tube PHONO preamp interference - RFI, EMI, bad grounding?

@filipm it’s unclear to me what you tried with wifi? Did you physically unplug from the wall all your routers, access points, extenders, devices that receive and or broadcast wifi and Bluetooth? Turned off all mobile devices (including phones, smart watches, tablets, computers)? This will help identify the source inside your apartment. You said if you lift the unit up the noise reduces? This can mean your downstairs neighbors have some sort of a device that can produce this interference. There’s just too many things…smart switches, smart devices, wifi access points, etc

Also, how old are the tubes in the unit? It would be interesting to change the tubes to something like latest production JJs or Gold Lions. Since you didn’t experience this with your solid state phono stage, if you don’t find and can’t eliminate the culprit, one of the simple options will be to go back to a solid state phono stage.

@filipm you have 3 tubes? And the noise is in both channels? I’m assuming one of the 12ax7 tubes is a rectifier? I would just replace that one to start with. 

Going back to ss doesn’t sound very appealing :)
 

Well there may be other tube units that won’t have the same issue. Also, pretty sure you can get a good solid state phono amp that would equal or beat your EAR in performance and noise rejection. 

@filipm

I doubt there’s this much noise in your power line that would cause this. The power supply in the EAR would take care of that. Your phono amp, tubes or cables act as an antenna that’s mostly what it sounds like. But anything is possible.

Also, just some notes from my experience rolling tubes…

I’ve tried Mullard, Tung-Sol, Gold Lion and JJ 12AX7 current production tubes in the Rogue ST-100 tube amplifier I had at the time and liked the tone and overall presentation with the Gold Lions the best. But every component is different so until you hear it for yourself you’ll never know.

@filipm absolutely…you have to try everything you can.
Hope you resolve this soon. Keep us posted. 

At this point the cure is worst than the disease. Dump this phono amp and get one that’s properly designed to not be susceptible to this type of interference at least within your setup. Seriously. You’re going to drive yourself nucking futs. 

@filipm 

There's an interesting point about the ARC though. When I changed the tubes (it's mk1), uses 4 pieces of 6922, the noise was picked up by the ARC too. It was just very quiet and only when the cage was opened. 

Are you changing tubes while the unit is powered on? 

@filipm 8 days later and you are exactly where you started. You have a broken or poorly designed component or the combination of the two.
You should reach out to the person you bought it from and start working thru some sort of resolution. If it’s too late for that, may be send it in to have a qualified repair tech have a look at it and determine next steps. 
Doesn’t look like you’re on the right track here…