ZBrushCentral

Strange bounding box lines appear around the brush while drawing on Higher Res.

Hi!
This may be a very newbie question but i couldnt find an answer to my problem on the attached image.

Is this a graphics card issue? (I have GTX 960) or by mistake i enabled a drawing mode and i see these vertical and horizontal lines? When i rotate around my model they dissappear btw.

Thanks for help.

Attachments

image-problem.jpg