Ok, is please bear with a little explanation:
My girlfriend had the master bath in her condo remodeled, and asked her contractor to install a new (GFCI) outlet. He apparently pulled it from the switch for the vanity light fixture. At the same time, he installed a dimmer switch for that same vanity light. The good news is there is no buzzing from the light fixture at all. The bad news is that the new outlet is buzzing and crackling like mad. These people told her there was nothing that could be done, and that it wouldn't hurt anything, it was because the dimmer and the GFCI amounted to two transformers on one circuit. This is a crock, but I wasn't around when the work was done. At this point I am wondering if anything can be done without pulling out the new sheetrock. The GFCI outlet works fine, it tests and resets normally, and you can use it nomally as well. It just sounds like an angry beehive. I was considering a lamp debuzzing coil, but my only experience with one of those, it made as much noise at this outlet is. Any suggestions?