First, the easiest way to zoom out is caps lock, it goes from planet to galactic view instantly.
Second, I've had the same problem, but while playing Spore. My guess would be something to do with the mouse, but that's just a guess. Is it something special, that would have its own post-shipping drivers to install in the comp? If so, try re-installing those.
A guess: When this happens in the game, (Single Player Fix) Save, exit, and reload, and see if it persists.
That's all I can offer as far as help.
Also, try PMing Kryo, and/or looking up the support page in the back of the Sins manual for better advice. (Hopefully)
If you bought the game online, the manual is a PDF listed under Stardock Games in the start menu, and the support site name is listed around 6-ish pages from the end.
Hope this helps!
-Twilight Storm