You said he's puffing up his beard and opening his mouth wide, can you take a video of this and link us to it? Putting it on imgur or youtube would probably be easiest to link us to. I doubt I'm right, but I want to be very sure that he isn't just gaping or even being defensive/scared for some reason. Some people mistake this for a breathing problem if they don't know what to look for, so I just want to be 100% sure before you spend money on a vet, because the video will only take a couple minutes to record and post.