Airbrushing Acrylic on Urethane, Fuzzy problem

Painting up my first ever Bat-Armor finally, woohoo. It's the Arkham Origins armor by Gauntlet FX. I'm using vellajo airbrush acrylic paint, I started by wiping down the armor with acetone and I'm working in a very clean environment.

i noticed after the first pass that the armor looked fuzzy. The fuzzy areas stayed darker than the non fuzzy spots no matter how much paint I applied. I happened to have some 600 grit sandpaper and with a lot of very light sanding the fuzzy texture does come off leaving the paint color for the most part, but not one hundred percent. Oddly enough the fuzzy texture showed up on the pec armor but not the ab pieces.

i think I can get it totally smooth but it will likely need reprinting and I want to make sure I didn't do something wrong that could have caused this. Any tips on making sure this doesn't happen again?

Update: talked to a fellow Bat-fan on Facebook that said holding the brush too far away can cause a dust build up effect as the paint drys before it hits the armor. Finished sanding the armor and the first pass holding the airbrush closer seems to have fixed the issue.