Hi everyone, sorry to bring back such an old thread but I'm Having this issue on PC (Windows 10 64bit)
Happens on all the amps I have on hand, Mesa Rectoverb, Fender 57 Custom Champ(5watt), Fender Supersonic.
Happens when connected front-of-amp on the champ or 4cm on the RectoVerb and Supersonic. Not that I ever thought it was an amp issue.
I was leaning towards ground, but I've tried quite a few different ways of plugging in power for everything with a few different surge protectors, also no surge protectors. Still, no luck but the hum did change slightly. (I think it did, it kind of oscillates anyway so hard to tell)
Have USB 3.0 and 2.0 on my workstation and tried both, (Have a Motu 828mk3 and Roland Octa-Capture I run via USB and those have no issues with noise)
Tried removing everything but mouse keyboard and Helix, no luck there.
I admit I did not unplug all my other USB devices when I installed the Helix drivers/Editor, so I'm going to try uninstalling and doing a more careful install.
I attached a little clip of the sound it's making. Helix USB Hum.mp3
Thanks for reading!
