If your sound card (device) is listed as default, you've got the latest drivers (or rolled back to a previous time), then it could be broken. If you've checked the master control (probably bottom right of desktop screen) and volume mixer (right click) and checked the sound scheme....
Can you remember the last time it was working? You could try system restore, but be careful, anything installed since then will be lost (sort of).
Yeh ive tried all that(i think),i had it up-graded from vista to windows 7 about 3 months ago it was working then,i did mute the sound and when i went put it back on nowt happened......
that was about 6 weeks ago and didnt bother me but im now getting fed up watchin you tube in silence:smirk:......
Hmm, if all software things, ie drivers, programs etc are not the cause then it might be hardware. Its hard to tell without actually being on the laptop itself