Hiss/White Noise persistent on Phones Out

On my QC I hear an Hiss/White Noise always present on Phones Out.
Try This:

  1. Turn On QC
  2. Create New Preset completely empty
  3. Disconnect instruments cables ( detach cable from QC, not from Guitar)
  4. Set Master Volume complete counterclockwise (0 %)
  5. Connect your headphone and hear…
    There is a hiss without connected.

the QC takes its ground from other gear- have you tried connecting it via USB or XLR?
Usually that’s more of a buzz than a hiss though.

Yes. I have connected USB and than also XLR to the mixer…
Nothing chage

Do you hear the hiss thru other outputs?
Are you set up to be able to record the sound?
What headphones are you using?

No thru other outputs there is no hiss.
Can I try to record but I’m not sure about results.
I use Audio Technica ATH M50X and Monolith M1060