Does anyone know why my wireless doorbell is now - after about two years - suddenly ringing on it's own? I thought my cat was doing it, but that's not it. There is a front bell and a backdoor bell. It seems to be only the front bell that rings on it's own. The part that plugs into the outlet is in the living room - near the front door bell. The door buzzers run on a battery. The batteries were replaced a few months ago. Any ideas why it's going berserk?