Can any one suggest why my sound card appears to have suddenly stopped working? Last week the sound was fine, but for no apparent reason, I can get no audio at all from either speakers or headphones. I have checked the headphones on my CD player, and my speakers are fine when connected to my radio & MP3 - so the fault must be on my computer. I have tried the usual checks as suggested in the Windows Trouble-shooter guide, but no success. Any help would be appreciated.