when i m attending a call(nokia 3250)..the sound is really less .i cannot understand what the other person is saying,,is der any software or way to increase da volume more ??

mmm... assuming you have had this phone for a while already , to my knowledge nokia 3250 has a pretty loud earpiece, it might be that you have something like metal filings stuck to the dome of the speaker, otherwise component failure is the problem. take it to a repair shop to have it checked out.

i forgot to add, there might also be slight oxydation on the headset connector on the mobile causing a "resistance" that could make your earpiece softer. you can try to plug and unplug your headset a few times to see if it helps. otherwise take it to a repair shop.