problems with altec speakers in my hp pavilion g6 laptop

Dear Sir,

I am Vignesh from mumbai.

I have an Hp pavilion g6 notebook pc.

It is about 3 and half years old.

 serial number : CNF1202D3F 

product number: QB406PA#ACJ

As you might be aware it comes with Altec speakers. Since the past 3 months I have encountered a problem with the speakers. The sound coming from it while playback is very harsh and unpleasant (as if some noise is getting added to it while playing the sound). Thus , the sound coming from it is not clear. However, it plays a clear sound when a headphone is connected to it. Thus, i feel that there is something wrong with the speakers.

Please assist me in troubleshooting this problem.

Thank you.