SNOWPIN'S PROFILE

author=GameOverGames Productions
Open command prompt and run this:
%SystemRoot%\system32\rundll32.exe "Path to ffdshow.ax" configureAudio

example:
%SystemRoot%\system32\rundll32.exe "C:\Program Files\FFDShow\ffdshow.ax" configureAudio

Then under DirectShow > Multiple ffdshow instances select "only one - check previous filter only"

If that still doesn't work, under the same tab add the name of the program executable to the "Don't use ffdshow in:" list, and check the box beside it if it is not already.

edit:
not sure if that's were rundll32.exe is still in Windows 7 if you have that though, so you might have to change that path too