Awesome, it seems color limit did the trick!
I never though that I could have problems with that I think because I never did I just used that to get rid of fireflies, well welcome new technology I guess

It seems karma XPU is really shinning

Thanks for the help guys!

Hey, I’ve encountered a similar issue. But I may have found the culprit. I believe it’s a backface culling problem. I could be wrong but without culling the backface in Karma Render Settings node, lights would treat the backface as normal surface, which means it will not know which side of the surface is the inside and which side is outside. When I turned on backface culling, everything just works. I hope it helps.