Would DirectX 9c fix this?

My video capture card software was working perfectly about a month ago when I still had DirectX 9a, then I got 9b when I installed Call Of Duty, now when trying to use that capturing software, I get a "Can't Get Device" error... I tried everything, reinstalling the card, the software, the drivers, running Adware, Spybot, Reg-Cleaners... Everything... Nothing worked.

I then went onto the website of the capture card and downloaded newer software, which just isn't as good as the older one which could be tweaked more. I'm thinking that maybe the reason for the older software not working is because I got DirectX9b over 9a... Would getting DirectX 9c fix the problem? I can't uninstall DirectX 9c so if it makes things worse, there's not much I can do.

Whenever trying to run 3rd party capture software like Premiere or VirtualDub I always get an error that the video device is already in use and might be because of WebTV, DVD players etc... However none of that stuff is in use, but I still get the error!

Any help would be appreciated.