The last OS to support Hardware accelerated sound was Windows XP. Anything after that does not support it (which is why Creative and Asus struggled with drivers for years). I know there is a sound bug though where some sound cards do not like the compression method used by the game. Look it up and see if they made the same fix for Fallout : New Vegas. It means basically either downloading the entire game sound library as wave and putting an ESM in or downloading a tool that converts all of the sound files.