ZBrushCentral

New Layer add noise problem

Hello every one! Today i confronted with a strange problem with layers in ZBrush. When i add a new layer is also add some sort of noice on surface of my model. What is it? And how i can fix it? Thank you.
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Attachments

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After.jpg

How large is the model relative to the Tool>Preview window? If it’s really large, that can create problems.

Also, which version of ZBrush is this?