Inner shadows are grainy

Hey everyone,

Whenever I render something that has inner shadow - see attached picture for example, I get this grainy look and the shadow becomes really bad.

I improved the render quality from "best" to "maximum" and also improved image quality on settings to high. but still struggling with this issue.

Does anyone has an idea what i can do to get a smoother look ? Did I miss anything ?

Thank you !!

Sharon

SolidworksPhotoview 360