I have a wireless one on the side door. Sometimes it rings all by itself.

I think when I had the attic painted with the solar barrier a couple of months ago that all of the pressure on one part of the attic flooring might have messed up this bell. It has a transformer in the top of the hall closet, and the bell itself is in the hall by the bedrooms. Scares the crap out of anyone when it rings, but we can tell it from the doorbell unit that is plugged in in the other hall for the other door.

I need a nap.