Sound hardware issues Windows XP

Trying to fix a sound issue with Internet Explorer and having issues. Have tried just re-installing the Internet Explorere 7 again. Got nothing fixed from that I have also tried to fix the sound by fixing the sndvol32.exe it did nothing as well. I get sound from Windows Media PLayer, iTunes, and Limewire pretty much anything not associated with the internet, can't even get sound from Yahoo Music. I have a laptop computer which uses a Fn Key to turn up the sound the Fn key works b/c I can still use it to adjust the brightness, the number keypad, and many other functions it just will not adjust the sound and I also have no sound control in my taskbar it has disappeared. I've tried updates from Microsoft, Windows, and cleaned my registry with my anti-virus program. I can't seem to solve the issue whatever the issue may be if anybody has, had experience with this before please let me know I can't do anything with no sound. I was getting an error with a previous anti-virus program stating that the svchost.exe had a bug so I don't if that has something to do with it.