In my home studio I had ground loop problems by connecting my guitar preamp / audio interface (line6 hx stomp) to my PC via USB and then to my monitoring speakers via jack, with an infernal noise. I tried in vain all the advice of the guides: quality power strip with IRF filter, quality balanced XLR cables, ferrite rings on all cables. The noise still present.
Then I found this miraculous device that connects between the PC and the audio interface, creates a new ground for the USB device and thus eliminates the loop and noise. It saved my sanity, I highly recommend if you have the same type of problem. It is compatible with high speed USB devices.