Well, it seems the problem is caused by a outdated 'openal32.dll' file inside your game folder. The game chooses to use this dll over the system one, so if it's an older version, it won't work. This file should not be there. 'wrap_oal.dll' can also be safely removed, that way the game will use the latest OpenAL dll's installed.
So, those of you who haven't tried the solution JackaBot147 posted, make sure that there is no 'openal32.dll' in your game redist folder, and that you install the latest OpenAL redistributable (which can be found
here).
If it keeps failing after that, then please please please report it. With your help I hope all these issues will be fixed someday.
Also, if it works, please report it too
@Schwarze Pest, you're most probably right, as IIRC the Audigy drivers ship with a native OpenAL driver (ct_oal.dll). You should find these dll's (openal32.dll, wrap_oal.dll -and ct_oal.dll in your case-) in the Windows/System32 folder. If they're not there, then your computer is doing some kind of magic I would be afraid of