World postion offset causing artifacts in all g-buffer layers

Attached is a screenshot of a material that I have a hard time debugging. Note that there are black spots showing up in all g-buffers in some locations. These flicker in and out of view depending on the camera location.

Any idea what could cause such artifacts? Or how to debug them?

Additional information:

  • The material compiles without errors or warnings.
  • It outputs constant values to all channels other than world position offset.
  • The material does not have these artifacts when set to translucent, even though it uses exactly the same input in the World Position Offset channel.
  • The WPO input has a Gerstner wave implementation, which notably does not use the camera location/direction anywhere, yet the artifacts are clearly view dependent.