Hi. I've had the Sony Wega KV27FS13 for about 19 or 20 months now. It's been a pretty good set overall, but lately I've been noticing a high pitched squeal that seems to be emanating from the TV. It doesn't happen all the time, or even most of the time, but I know it's probably connected with my TV or my cable box (analog cable), because the squeal disappears whenever I shut everything down. Whenever I power up again, it's usually fine, but sometimes the squeal will come back without warning. Does anyone know what this could be? Thanks!