Really helpful.
I noticed the flashing only when the Rim Light is enabled.
Can you reproduce this artifact/glitch when it is disabled?
(I’m checking the video again to make sure I’m not mistaken, but I wanted to get an answer to you quickly before I head out…)
Also, you can make videos private/unlisted on YouTube and you can always destroy them later.
EDIT: Yes, it might be the Rim Light. Try to reproduce this issue with it disabled. It’s the only light that was enabled that produced the error. Any time you disabled it, I didn’t see the artifact.