I don't know if it's true or not but I can believe it. I've heard that dogs can hear things like mice, termites, etc, in the walls and sometimes that is what sets them off. I don't know if its a possiblity at all, but I thought I would throw that in. Layla is pretty good. Alvin loves to get her worked up, normally all he has to do is make faces at her and she barks and runs in circles. Wierd pup. Wish I could help more.