Hielor on Orbiter-Forum brought up a bug in OrbiterSound. When you're your in the external view with OrbiterSound activated
using wither Vista or Windows7, and change window focus the game CTDs. I can only test under Vista, but I can confirm that
changing window focus causes a CTD, but only when Orbiter is in an external view and you're running in windowed mode. This
also happens whether the silence of space option is enabled or not.
Here's the original topic started by Hielor:
http://orbiter-forum.com/showthread.php?t=8897