My Peek a Boo does that when he gets excited. On the other hand, he was just diagnosed with CT and I don't know if it's related to that or not. I haven't seen it listed as a symptom, so I'm guessing not. He also coughs after drinking, wakes us up hacking at night, and can have a coughing jag if he gets too excited. This is one step past the loud panting noise.
