My laptop speakers stopped working..plz help me

Well, internal electronics isn't specifically my area of expertise but on the surface it sounds as though there is either a faulty connection or a faulty speaker coil that is heating up after a short time. Speakers are circuits that current passes through to create sound, so the process generates heat just like it does in any other circuit.

While the connection might work at first, if there is a barely connected wire or one with a break that is partially touching, it might work at first but after heating slightly it loses it's contact and fails to work. It also seems like this is a common issue on your model of laptop since I see about fifty similar threads when I google it.

That would lead me to believe it is probably due to poor design or a design flaw that is common to that configuration. If that is the case you will likely need to replace the internal speaker, or you may simply have to either use the headphones, or get a portable speaker than can be connected to the headphone jack. If the laptop sound is mainly used when at home you might also choose to just connect it through your stereo or entertainment center speakers, if you have any.

Since that model is an Indian model I must assume you are either in India or from there and might not have such electronic devices but you can surely find a relatively inexpensive external laptop speaker to use if you are unable to replace the internal speaker. This is not likely to be a driver or sound card issue since it does work for a short time and also works using the external jacks. Good luck.