Sunday afternoon we heard a beeping, real sporadic, that soon turned into an unbearable buzz. Wife and I both have lost hearing in one ear each, and we were going crazy going around the house looking for it. Could pinpoint it to one room for sure, but could hear it in the kitchen too. Would have tried closing off each room, but we took the doors off to facilitate her wheelchair. After an hour of unplugging things, and checking everything that was electronic we found it. I laid the old smoke detector on a high shelf and it was echoing down the back hallway, dang. Didn't even realize it still had batterys in it. Later I started hearing another pinging sound, same go around, she was bothered by it a lot more than me. Seems when we reset the time on the microwave we triggered the food is done alert, got to love this modern age. Makes ya just want to wind up the wall clock just to listen to something that you know what it is, as long as I turn my left ear to it. Nobody else got this problem?