Bet it is coming from the Ethernet connection. I have had similar ground loop issues. Amazingly, I just ameliorated it by hooking up a hdmi cable to my blu ray player from my tv; the blu ray feeds through coax signal to my Yggdrasil DAC, which is also connected via USB to a music server connected to Ethernet.
what happened to the Belles website ?????
Its been a while since the Belles website (power modules) has been operational. Anyone knows what's going on?