Thats why.
Well you have my old problem, you must update you drivers for get the sound again working.
There is a Bug with GTA3 and GTAVC where if the game crash with EAX activated, then EAX and the sound card will not be able to work again.
btw, i had that problem too, i had a sund balster live, an audidy and now an audigy 2. `
So don`t worry, thats the solution, hope i helped you.