Laptop sound is not working

Hello,
The sound on my laptop (Toshiba Satellite-L 300 series, with Vista Ultimate) just stoped working. There are occasional cracking sounds coming out especially durring booting. I have tried to re-install the Realtek sound driver, did a system restoration, checked all my settings again but nothing seeems to work. My head-set sound is also dead, but when I check the status of sound on the control pannel, it shows that it is working just fine. Does anyone have any other ideas? I have checked the mute too, so do not go there either!!! Please help, I love my music too much!