In SMPlayer or VLC you can change your Audio to use different outputs/settings.
In a root terminal screen (Ctrl-Alt-F2) Old Sounblasters are initialyzed by:
modprobe sb
modprobe sb8
modprobe sb16
modprobe sbawe
They are not all available anymore, for you to check one by one....
setting up the card with
alsaconf
Go back to your Graphic screen with Ctrl-Alt-F7(or F8) and check your audio.
if you found the right one you can add (as root) sb, sb8, sb16, or sbawe to
/etc/modprobe.preload
not playing sound from divx
But you have sound allready, maybe missing
win32-codecs-all
Install from Synaptic
Good luck
Ed