Vector Displacement Appears Clipped

tiled vector displacement appears to have camera clipping, but still has the base shader, just no displacement… if camera or object are moved (up, down) respectively then the issue goes away, so it is definitely something to do with how close the camera is to the object…
(i tried near far plane, tried auto render clipping, and not auto render clipping)
Any thoughts?

Can you get us a scene? It’s mostly guesswork when we don’t have anything to look at that shows the problem.