From what I read that is what I figured. But I unplugged every thing that emitted any kind of RF signal and got no change in the light. I have also never seen it out, ever. I don't have any special lights (a couple fluorescents and incandescent), I have a small old (1941) house and only 2 neighbors within 100 feet. I can't see any other way to clean up interference. I have allot of high end theater equipment, Krell and B&K powered by 2 - 20 amp dedicated breakers with isolated grounds, a voltage regulator and line conditioners on my theater so it should all be very well isolated from the house. The RFX 6000 is just on a normal house plug across the room.