Where can i download the most recent driver for my Soundmax sound card?

Im a producer\dj and have just baught a new set of monitors (speakers). However when connected to my computer the low tones dont seem to exist. Basicly i have no bass. i phoned up the shop i had baught them from and they said i should updated my sound drivers, however i cant find any. does anyone have any ideas. It would be a great help.

Thanks