Sount Coming in headphones as well as speakers

[Jatin]

Hi

I have a Toshiba A135-S2386 laptop on which i am using ubuntu 9.10 since 
the last two months. Upon some update (i dont remember which one as i do 
it weekly once) , I am getting sound in both my headphones as well as 
the audio speakers of my laptop. The normal way would be get the sound 
in the audio speakers when i insert the headphones.

How to troubleshoot this ? Please help.

Thanks
Jatin