Problems with Logitech x-530 5.1 surround sound system.

The other day I ordered a brand new surround sound set for my computer, overall I've been very happy with my purchase with one exception. The center speaker. I have tried everything I would know how to do from messing with audio settings to testing it on other devices. Through testing it on my TV though I was able to figure out that the central speaker does work and it's not some kind of technical problem but then there comes a more confusing part about how it handles on my pc.

So in what must have been about my billionth time trying to mess with the audio settings I enabled the central speaker with no noise, as usual. So i tried something different by disabling it, after i unchecked that box for that speaker and tested it I got sound out of the central speaker. So after trying to play a game that uses the central speaker for dialogue and character voices such as Assassin's Creed: Brotherhood; I could see that the speaker didn't work, much to my dismay. So I have come here for help and any would be appreciated. I've reseated the cables a thousand times and even re installed my audio drivers several times. I don't know what else to do!

My pc is running on Windows 7 x64 my audio card is a fairly recent realtek card that came attached to my motherboard which I have also examined and nothing seems to be wrong with that. I'm not sure as to the exact model.

So thank you for any help you may be able to provide, because I'd like to be able to use my surround sound to its full potential!