Hello, I have a small problem. I have 3 yorkies and I just got a complain from the landlord that they are barking way too much when I am gone. They bark if they see any people by the drive way or if they hear people in the hallway. I would like to know if anyone has had the same problem, if so what did you do? Is there any device that I can buy that may help? I'm not interested in any collars. Any help will be highly appreciated!