Lightmap in LODs is "jumpy" - some LODs are dark when they shouldn't be

I’m having a problem with lightmapping here:
My scene is using nearly completely the Unlit/Lightmap Mobile shader. Most of the geometry is static and using only non-directional baked GI only.

Many objects have LODs set up as well (also using the unlit/lightmap shader). The lightmapping UVs are created automatically by Unity.

A lightprobe group has been set up for the scene as well (as per documentation lower LOD stages use lightmaps instead of lighting).
I’ve manually gone through the scene and set up the lightmap sizes to be evenly distributed.

When the maps are baked - in LOD0 everything looks good and as expected.
But then for in some of the lower LODs the lightmap gets drastcally darker for no apparent reason.

When I switch into “Baked” mode to check the lightmap size and zoom in and out it is even more apparent. (edit) It seems that the dark lightmaps occur in LOD1 only. LOD0, LOD2 - LOD4 etc. are apparently fine.

Ist this a known bug or is it a setting?

I’m on Unity 5.3.3f1

(edit) okay - never mind. For some reason it seems that the lightmap wasn’t done baking or wasn’t displayed correctly across the rest of the scene (it was all displayed brightly lit). For some reason only LOD1 was displayed with the lighting information until the rest was displayed with the baked lighting as well.

How did you fix it?

This thread was created nearly six years ago. Please create a new thread if you are running into a similar issue.