No sound from laptop speakers. (amends previous question)

Hi, I bought Dell Inspiron 9400 laptop couple of months ago which came pre-loaded with Windows XP Media Center Edition. Suddenly something went wrong which resulted in No sound from my laptop’s built-in speakers. As per troubleshooting I checked each and every settings under control panel for sound and audio and everything seems to be fine. Also when I plug in headphones to the jack I can hear clear sound but it wont work in the built in speakers.

I tried searching for some help on web but dint found anything related to my problem. Hope you guys understood what exactly is the issue on this laptop. Please help.

There are several articles already available on this forum regarding this same problem. yoiu should have already checked the same. Anyways, i'll suggest you to first checkout this which is very similar to your issue: http://forums.techarena.in/windows-software/1366989.htm

Apart from this did you re-installed or updated your Sound drivers? If not, download the latest audio driver from Dell website and install. Did you test the audio/sound with dxdiag?Is the proper device listed in Device Manager?

No sound from lenovo 3000 g430 laptop speakers Windows XP Support