Help! Tiny bubbles appearing in Rustoleum's Chalked Paint

I bought a can of Rustoleum Chalked Paint to finish several projects I'm currently working on, in Linen White. First coat went on fine, and I still needed a second coat. That seemed okay too. Still a few spots that needed touch up and I went to put on a third coat, and I'm getting tons of tiny bubbles. They don't appear in the can, just once painted on. I tried switches brushes, tried stirring the paint more, tried tapping the cans to see if bubbles would rise to the surface, and nothing seems to help. Anyone else had this happen? Ideas on how to solve it so I can get my final coat on? I had sanded the pieces before painting too, to help with adhesion.

Thanks for any advice!