Weird squares in final render

Hi,
while V-ray GPU is so bugged, I decide to switch to V-ray and in my first project I get a weird issue.
Does anyone know why this happens? I use only HDRI dome light in the scene.

Thanks

Which V-Ray version build do you have installed?

5.20.02. 00001

Is it possible to strip down the scene and send it to us so we can take a look? Mention me in the message and include a link to this thread.

Just did it. Let me know if there is a quick solution

We are aware of the issue. It’s already logged (internal bug-tracker id: VMAX-10356) for developer investigation.