Sorry to hear that Buddy is ill. A couple of things came to mind when I read your post besides a respiratory issue, could he have air sac mites? The other thing is a problem with the thyroid. These 2 things came to mind because of your mention of the beep sound, with both of these problems you can hear weird sounds coming from them. I would keep Buddy in the cage and not let him out until you see the vet. How is he acting otherwise, is he eating?