We've had our x10 security for 6-7 months with no problems; however last night we had a false alarm at 1:30 and again a couple of hours later. We don't have the motion detectors, only the door-window sensors. Both times, number 8 on the console was lighted (a window), we checked it and the window was secure (as well as all the others). A week ago we changed all the batteries and added some keychain remotes. Anyone have any ideas why we could be getting these two false alarms?