I'm using a Sonic Cell as my audio/midi interface and I'm getting a crumpling cellophane type of sound through the monitors with a rhythmic cycle to it . I've narrowed it down to the USB connection from the SC to the computer and doing some surfing it apparently is a ground loop type of thing. The USB cable carries a ground wire in it. The first thing I did was plug the computer, keyboard, SC and the mixer into the same power strip so they all have a common ground but alas no change. It also doesn't matter if I use balanced cables or not.

My final test was unhooking everything from the SC except for the USB cable and my headphones. No noise until I plug in an audio cable into either the audio input or output on the back of the SC. The instant the cable makes connection I get the noise until I unplug the USB even when the cable isn't plugged into anything else like my mixer or keyboard. The SC works fine as a stand alone module, it's when I use the USB I get the noise.

As for possible solutions I've seen recommendations for a USB Galvanic Interruptor gadget that goes between the USB cable and the computer. The other possiblity is to use a power conditioner box like the ones by Furhman folks talk about. Both of these are not cheap, they're in the $50-75 range which seems like a lot just for a little noise.

For another hundred I could get a new dedicated PCi or firewire interface (my mobo has firewire) and bypass the USB and just use the SC as a midi sound module like I was doing before my EMU 1820M died.

Any suggestions?

Bob

Biab/RB latest build, Win 11 Pro, Ryzen 5 5600 G, 512 Gig SSD, 16 Gigs Ram, Steinberg UR22 MkII, Roland Sonic Cell, Kurzweil PC3, Hammond SK1, Korg PA3XPro, Garritan JABB, Hypercanvas, Sampletank 3, more.