Comment 1 for bug 1037593

This is a problem with Compiz, not Unity. and this happens when reverting to a resolution less than your current one...the most common ones are 640x480, 1024x768, and 800x600. This DOES NOT happen with Unity 2D (because it doesn't use Compiz). This also happens with native games as well. So it's not a problem with wine.

a workaround is to switch to the resolution of your game BEFORE you run it..:)

p.s I really hope this gets fixed..it's been an issue for a while now.