Jojodayolo

@reginaldStjohnThanks for the quick reply. So I tried the things you said, now my noise is gone on the XLR jack, but it's still on the 1/4 inch output. Right now I'm using an instrument cable that I think is suboptimal. Now with the working XLR it's fine for me, but it would be interesting to know if the balanced cable from Helix 1/4 inch to my interface would solve the problem. Another thing I discovered is that if I connected the Helix to the Mac via usb, but didn't select it as an input or output device in Logic X, the noise wouldn't be there. The moment I select the helix in Preferences>Audio>Devices (no matter if as output or input device) and click "Accept Changes", the noise appears.

I have kind of the same problem. I have always a high pitched noise when the usb is plugged in but only on the 1/4 inch and xlr outs( dont know if its on the headphone out). But if I record something over the build in interface I have no noise. I use a macbook pro with Logic X. Tomorrow I can check if there is the same with a Windows PC and Cubase LE 9.5