Screen Dirt off not working.

Anybody else having trouble turning the screen dirt off? Off or on is the same, dirt on the screen after a few laps. Thanks

 

I have the same problem

 

Me to! ;-)
Is there a solution existing?

 

This effect is great when it works. In Assetto Corsa adds a lot of realism, but here it makes no difference if you select YES or NO

 

I know what’s happening. In cars with rear camera, it is the camera screen what becomes dirty gradually, instead of the car screen