MCH,
I had exactly the same problem a while back with the drivers for my SB live card. It is a Audigy NX card. The SB cards do seem to need the original drivers to operate properly. I 'lost' (read misplaced...) my installation CD's and as a result had lots of problems trying to get the card to work again. I eventually got a copy of the original drivers from Clancy. (bless her soul...

)
Before Clancy sent me the right drivers I spent hours surfing the net trying to sort out latency issues with all sorts of drivers. the only drivers that got anywhere near solving the problem was the ASIO4all drivers.
If you are having latency issues it is a hardware issue with the drivers not being able to syncronise the internal clocks of the various components being used in your recording chain.
I was never able to completely solve the latency issues without the use of the original drivers, but like i said ASIO4all got close. Maybe I did not spend enough time on the issue.
* Are you running the original drivers?
* Do you only use your soundcard for recording or do you have other components connected that might be using world clock times?
WernHalen