I have strange problem in Blender 2.72 - instead of some edges i have small black stripes on surface where there must not be. I do not use noise texture in this material.
Here is rendered material
At first i thought it is problem with wrong direction of normals.
I checked normals and they looks correct
Then i apply the same material to default cube with four level of subsurf and result just the same - black stripes instead of some edges.
What can possibly go wrong? How do i fix it?
Here is material nodes