I brought my Blackfinger and Hum Debugger from the studio into the house to play around. The Blackfinger developed an annoying buzz. After reading this forum, I took the Blackfinger power supply off the power strip and plugged it into another outlet and the buzz disappeared. Thanks to you guys for solving my problem.

I realized that the reason I don’t usually have this problem is that I don’t use an ordinary power bar on stage. I have a surge protector that, instead of a power-strip, has six power cords of various lengths. I have no idea where I got it, but it might work for you,

Whiteboy Slim