Hiss problems and general electric buzz problems. Playing outside on a flatbed truck, I had a buzz through my Pa so bad it blew my breaker on my guitar amp. Fix: Some guy on a WW11 Harley drove up (Time frame 1985) and asked me the problem. He then took a Horseshoe stake and pounded it in the ground, took a thick wire or a metal coat hanger and hooked it to the generator. Hospitals and many studios all use a third AC ground as does anyplace with a lot of sensitive electronic equipment but making sure your house has a good basic AC ground is also very good for elimimating unwanted buzz. I also always used a 12v batterys instead of pluging my foot pedals into the AC your out there when in an environment your not sure of. Take or leave it! My name is Bob, by the way and hello to everyone.