It sounds like you either have a clog or a bent needle! First, try soaking it in airbrush cleaner and the rinsing well in warm water. If that doesn't work, you may need to disassemble to check for a larger clog.
This happened to me a few months ago, just about drove me crazy! (I had sprayed luster dust thru it, and THOUGHT I had cleaned it good enough-I was WRONG!!!) I broke my airbrush down into a dizzying # of pieces looking for my problem. Finally I found out there was a clog in the tiny nozzle that holds the needle in place, causing my needle not to seat well.
If you have more problems, post back I'll see if I can help.
glenda
can you increase the pressure? not enough pressure leaves a grainy look. a bent needle will make bigger random spots.
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