My DAW is a full tower PC with a self contained power supply. It is shielded on all sides but the bottom.

I'll have to check on the type of ceiling light in my room. How do you do an earth/ground lift on a USB line?

There is a Cat 5 Ethernet line running through the rat's nest behind my studio desk. Could that be a source of interference?

ETA: There is a laptop in the room. It's on another outlet and surge suppressor, but presumably on the same breaker.

Last edited by Ryszard; 09/16/14 03:17 AM. Reason: Add information

"My primary musical instrument is the personal computer."