Terrain Blacking Out

Level 2
Feb 29, 2008
On the map I am currently making, whenever a large portion of the map is reavealed, either through an ability like flare, or the cheat iseedeadpeople, the terrain turns black, and the units go black too, with few details remaining. It affects all the visible terrain, and is quite a giant and noticable bug that rather runis gameplay. The terrain and units go back to normal after a few seconds (or in the case of the cheat, when the cheat is disabled), but is still a large problem I would like to solve.

Does anyone have any ideas towards what I could do to fix it? I know I could probably just remove flare and any other revealing abilities, but I would much rather keep them there.