I've got this annoying buzz inside my small practice combo amp. It's a Kustom (ugh, I know), 10 watt. So I was thinking that maybe I could just open it up, tighten a few screws etc until I find the problem, but is it really that easy? Should I take any precautions while opening it so I don't get electrocuted or anything? Obviously I have to take it out of the power, anything else? It has a warning sign on the back that says not to open it in case of getting shocked... Any suggestions?