No sound at all from HP pavilion laptop.

Hello,
On my HP pavilion dv2945se the speakers and headphone jacks are not working. On the volume icon there is a x symbol. Almost like the mute icon but the computer is not on mute. When you mouse over the volume icon it says no audio output device is installed. What should I do to "reinstall" my speakers. I already tried to redownload the driver but that didn't work. It may be the sound card but im not sure, if it is how would i fix it?