Ok, If you sure everything is setup right, proper settings and installed correctly, and its not giving you any sound, to uninstall the card from the device manage and remove any SB sofware from your PC. You can use this: Guru3D - Driver Sweeper
to ensure everything is removed.
Then go to SB and download yourself the correct win7 64-bit drivers and manually install them. And see if that fixes it, I know it sounds like alot but shouldnt take long at all.
BTW, what is the exact model just SB-Fi ? Not titanium, extream, or platinum?