Yes, it making the sound when not running. Sorry I wasn't clear. I heated an item in the microwave and opened the door and removed the item and then closed the door and heard a humming/buzzing sound. It did not make the usual sound like it does when it is running, and the turning table inside was not moving and the interior light was not on...it was just a humming sound. This humming continued while I was away from the house and when I returned a couple hours later the outside door and interior of the microwave were both hot to the touch. So whatever is making that sound is generating energy enough to heat the unit. Thanks for any input.
Rene
July 2013