Could be flower thrips. These tend to peak toward the end of the first flush and may subside, or not.

Thrips.

If you want to do something about it, welcome to the world of spraying. I've tried a number of things through the years, but nothing seems to work as well as a two-punch combination of Conserve (spinosad) sprayed all over, along with finishing up with spraying Avid on the buds. This is done weekly. More often might work better, but I simply can't manage the task of spraying during the week.

The Conserve helps to keep the general population down, but it's not enough to keep the buds/blooms clean. The Avid is important. Its action is trans-laminar, meaning that it will penetrate through the multiple layers of the bud. That's the only way you'll get the thrips once they're in the buds.

I've tried everything else - imidacloprid, orthene, Conserve by itself, Avid by itself and even some other combinations of insecticide. Nothing works as well for me (and does less damage to beneficials) than the two-punch combination.

Rosemania has some new stuff called Naturalis, but I haven't had a chance to use it yet.

Of course, I never thought of looking for thrip. It hasn't been a real problem here for me before. Thanks for the tips.