NavMesh PathInvalid below specific radius

Hello,

I've got a working navigation system set up for my robot simulation.

Well... at least unless I don't decrease the radius of the baked nav mesh (i.e. enlarging the walkable area) below a specific value and re-bake. That's really strange. Increasing the radius and hence reducing the walkable area's size however works like a charm. (still works but doesn't matter anymore)

Debugging NavMesh is a strain. Is there a way to find the actual reason for the PathInvalid status?

Thanks!

Update: This happens below a specific radius (approximately 3.69). Contrary to my first assumption that basically decreasing the radius caused this error.