Ground noise using XLR ouputs

My QC has a noise situation when I connect the two XLR outputs. The output that emits the background noise is on the right while the left is not. I thought it was one of the cables but not because when I use one of them interchangeably there is no noise and it only occurs when both are combined. How can i solve this?

what else is connected on the same power outlets?
Have you tried the Ground Lift on the outputs in the Swipe-down I/O menu?

Only my laptop and a monitor FRFR. I tried ground lift and nothing happens.

Is your laptop connected to the QC by USB? If not, can you test it with a USB cable? That occasionally helps w/ noise, but really the XLRs connecting to a grounded device should do the trick itself.
Just trying to check all possibilities.
What is the background noise- hum? Hiss? How would you describe it?
Is it present if you don’t plug the instrument in?

I don’t use the USB connected from QC to laptop in stage. This, only happens when i run stereo.

Using the ground lift switches on the XLR outputs, as @xush suggested, have you tried all different combinations, e.g. one-on & one-off, switching which output is on/off, both-on, etc…?

What are you connecting your XLR outs to? Two monitors, mixer? Does whatever you are connecting to have a grounded plug? If you are connecting to two monitors, try flipping the ground switch on one of them if they have one.

I would try actually swapping out the cables with two other different cables. This should be a more thorough test for eliminating the cables as the issue than just swapping the existing twos’ outputs, or just testing individual cables across a single output.


I tried different combinations with the ground lift. I’m connecting to a mixer (Behringer XR 18). I tried changing the cables, I used the left output only and there was no noise, the right only and there was no noise.

Time to talk to if you haven’t yet.