Tonight a high pitched whistling like sound began and is continuing in the kitchen. At first we thought it was coming from the fluorescent light fixture but we unplug the lights and then turned all the fuses off in the entire house one at a time, and the noise continued. We're stumped as to what it might be. If anyone has any answers or advice, it would sure be appreciated. I'm not even sure who to call about this, so please advise and help solve this mystery... Many thanks.