How to find out if managed DirectX is installed?

[C# Programming]

Thanks to some help in another thread I found out the reason an audio app is not working on some machines is because it requires the managed version of DirectX, which is not installed on most computers. Is there a known-good way to detect managed DirectX, specifically DirectSound? I know where the files are stored on the machines we've checked so far, but it would be nice to have something a little less haphazard.