Hi @nickholl ,
If you’re referring to the hard edged artifacts under the brush cursors in that image, this could be caused by a number of scene settings in your file in certain scenarios, for instance a Dynamic Subdivision + Sculptris Pro combo. It could also be caused by using an obsolete version of the program that is missing fixes present in the current version of the program. There was an issue related to Lighting Distance that was fixed not too long ago that could also produce this effect in certain circumstances.
Until you contact Support and fully document the issue, including all settings being used in the file, and let us have a look at your installation information, all I could do is make guesses.
I’m going to close this thread to eliminate any expectation of further help here, and to encourage you to go where this question can be quickly answered once sufficient information is provided.
Thank you!