Animation problem: flicker, black dots, fireflies


I have a problem when rendering an animation.
Some portions have a flicker. black dots, fireflies.
Can’t seem to get rid of them. When using HDR they don’t show up, only when i’m using Areas. I’ve rendered at 500 samples, no caustics, filter glossy 0.03.
Here are 100 frames @ 20% 4K

Thank you!!