i've had the same problem, it has something to do with the MP3 part.
As soon as i get into space and go to external camera, orbiter crashes to desktop while loading the mp3 music file
(default os music)
i managed to fix this by completely disabling Mp3 music in OrbiterSound's config.
Windows XP, Althlon 1300, 312 mb ram, geforce 4mx, directx 9.0c
Voyager