So I know we have a lot of ZiM fans on the site, and today I was googling around for Gir sounds when I came across this. Apparently it's Rikki Simon's (did Gir's voice and worked as color designer on Invader ZiM) blog. His wife and him are both artists and have a studio together, so that's what it really centers around, still some fun reading.
After reading the "Nickelbloated" post I went through some of the comments, and he replied to a lot of them. He's got asthma, apparently, and one of the replies had this:
"On a funnier note, my bad lungs are the reason why GIR’s enthusiasm for inhaling every last drop of a Suck Monkey beverage always ended in coughing spasms for the character. Those are my actual asthma spasms, recorded for everyone’s pleasure."

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