Since the animation speed and movement settings are both 0 the noise isn’t animating or moving. If it was you would see the “fizzing” effect even when the object wasn’t turning. What I think is happening is the bump texture catching the light along the edge as the object turns. I can’t duplicate it with a standard material and renderer with your bump channel settings and a default luminance channel so I’m guessing your render settings are also involved. Could you post the project file?
Thanks for sharing the file. You didn’t have the Luminance channel settings with your original post, but now I see that you are using a cel texture with “Use Bump” enabled, and that is what is causing the fizzing effect. The render settings aren’t an issue.
If you want that grainy shadow look to remain still when the object turns you’ll need to get rid of the bump in the material and try to get it with lights and shadows, which could be an interesting endeavor itself. As long as the bump is there, when the object turns the light will catch the changing texture and cause the fizzing. What is the look that you’re going for?
Glad to help. Some things you might want to play around with are adding noise to a light, or possibly creating an overlay that doesn’t turn with the object. Just some thoughts — I’ve never tried to do this before so I may play around with it myself. And if you’re lucky a brighter mind will chime in.
Good luck with your project. I will write back if I come up with anything.