Dell Inspiron 1700 no sound

while listening to a mp3 from a music web site, i had inadvertently gotten my leg caught
in my lap top speakers and pulled out the jack . When I hooked them back up I was unable to get the right speaker to work unless I played with the jack.

I unhooked the speakers thinking I could still listen via the built in speakers.


I now have no sound! What would have caused this? Do you think a wire is loose ? all the controls show the volume up and the mute is off.

Any thoughts help ideas many thanks