Hello-
I recently had a similar scare. It looks like your plants are pretty early on in flower. So that is unfortunate. I was recommended to clean the leaves with a hydrogren peroxide solution. I used 1 part peroxide 3% and 2 parts water. I sprayed each leaf and then wiped it off.
Also, check for mold/mildew in your buds. If you see any webs or strings in the buds...remove those ones.
Those were the suggestions that were given to me. Best of luck.
I would also consider someway of improving air flow around the plants...maybe set a fan nearby?