this will happen unless you update the driver correctly. happens to me. this is what i do:
- starting from scratch.. either after a format or at least get rid of every audigy program/driver you can.
1) install using the cd and select only the programs (ie. surround mixer, etc) you will use. this will also automatically install the driver off the cd. reboot.
2) go to add/remove programs and 'remove' the audigy software you just installed. when it asks you, unselect audigy drivers, but leave your programs selected so they'll remain. reboot.
3) cancel through any 'found new hardware' windows. install the latest web driver package. reboot.
this works for me. if it doesn't for you, you could also try moving the sound card to a different slot. i had problems until i moved it up one slot.