I have a 3 year old opener that will open and close to varying degrees all on it's own... middle of the night, middle of the day... anytime. And often when I open it, it will go up half way, back down a few inches, back up all the way, back down part way, up, down, up, down, stop, start again... you get the idea. I've removed the battery from the keypad, disconnected the wall button, and erased and reset the hand units... nothing has helped. Any ideas??