Sorry! :S What I meant is… what I would do to eliminate the problem is to reduce the whole lighting into minimal and build it up from that… So what I would do is keep just your main lights (skylight + directional if possible ans set 0 intensity meanwhile to the rest) reset all the unnecessarily (“fancy”! ;)) settings on these main lights (such as light angles and indirect light intensity…) and see the result… with 43 (or 6) lights + it’s more difficult to trace what causes the issue… IMO!!