Static Mesh displays black splats at render time

I’m using UE5.3 for Archviz, and ending up with these black splats on my building, which is a static mesh. The black splats only show up in some cameras, mostly when closer to the building. All cameras in the level have the same settings and exist inside of a Post Process Volume which they defer to. The black splats ONLY appear when I hit render in the render queue. They do not appear in the viewport.

Any ideas? I’ve Googled and read/watched at least 12 different threads and videos and nothing has resolved this for me yet.

1st image is the rendered look. 2nd image is the viewport.


Adding a clue:

It seems to happen when I have the High Resolution render settings enabled:

One more clue:

It happens with only half of the contrast (the black appears as dark gray) when I have High-Resolution turned off, but anti-aliasing turned on: