No Sound

Im trying to get the sound to work on my speakers. I have windows xp sp2
and they just recently stoped working, they used to do this sometimes but after a restart the would work, not the case anymore. However when i plug my headphones in they work but I cannot adjust the volume, they have the same volume no mater what, i have the creative gigaworks s750 speakers. I recently had a bunch of viruses. Ive tried reinstalling the drivers, but to no avail. Any help / guidence would be greatly appreciated. All the cables are connected correctly, i just checked