I would startt by completely uninstalling the drivers, cleaning the registry and removing the device in control panel. Reboot and then reinstall the drivers. You might want to check and see if you are having IRQ bandwidth issues with the soundcard and some other pCI card. If I were you, I'd do what I suggested above and then put the Audio card into another PCI slot after the drivers etc. have been removed and then reboot and install the drivers.
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