Weird clicking sound

I dont know if this is a big deal or not but everytime a door is opened or closed I hear this weird clicking or fluttering sound comming from the vent to the left of the steering whell.  It almost sounds like a trapped moth or something.  Its been doing it for about 3 weeks and I cannot figure out what it is.  Anyone have any idea?

Try using a shop-vac on the vent to see if you can pull anything out.

this may sound weird but if it's only doing it when you open or close your door...  maybe it might be your check arm worn out or even loose causing the sound to go up the pillar... just a thought..
 
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