Light sources disabling after bake.

I am experiencing a very weird issue with the Progressive CPU lightmapper. After baking my scene some lights are randomly disabled. They simply do not make light and they do not appear in reflections. The only way to re enable disabled lights is to delete them and duplicate another light and place in the location of the old light.

Picture

All the lights worked prior to the bake.

Edit: Enlighten didn´t fix the issue either.