While attempting to switch off my Subwoofer (which I've only had a couple of weeks), a small shock happened when I touched the mini-toggle. Now, my sub only makes a buzzing noise when plugged in. I can not get the buzzing sound to stop. Even if I turn the mini-toggle to the off position, it still buzzes. The only way to get it to quit is to unplug it from the wall. I checked the fuse and it's still fine. Any thoughts?