I just had a bit of a scare with my GK MB210, I was playing it whilst my daughter was using a sewing machine off the same electrical socket point, there was a loud crackling noise and buzz coming out of the amp intermittently, I was expecting the impending death of my amp then realised it was happening every time she pressed the sewing machine pedal ! At last weeks gig I had some strange intermittent cricket/grasshopper like chirping noises coming out of the amp (there were no grasshoppers LOL) but put it down to having a lot of other equipment near by, ie, PA system, foldback monitor system etc . This leads me to my question, is it right that other electrical equipment can interact with my bass amp and if so what can I do to stop it, if its not right then what do I need to do, is the amp faulty/not suppressed ?? I did read that digital/class D amps switch on and off many times a minute so is it possible that other current draws on the same plug socket can cause this ?