I was playing a gig tonight and was getting noise interference when ever I would click any kind of boost whether it was from a tube Screamer, GE-7, or compressor. The same thing happens when I practice guitar at the computer, I will hear something click on through the amp(like someone turned a light on or something) and then I will get this hum through the guitar. It will only stop if I hold the guitar in certain areas of the room.
MARTY FRIEDMAN--"It’s a lot easier to be technical than it is stylized; it really is... But I think it’s a lot more rare to have someone who’s really got their own sound because that’s something you can’t practice."
It will be the UV lighting at the venue and from your PC monitor/ other electrical gadgets

Only way to get rid of it is to gate until it goes