Hi why do you think so Shikha? Did you try rattles, music toys etc? In a silent room when baby is active try clicking your fingers near to his ears and see. If you still have doubts then consult Paediatrician but let me tell you, As a new mothers we get all these doubts and worry for nothing. So relax .

Plz record at once his activity against TV volumes and mobile phone rings ...after then check wat he react ..and plz cunsult with a child specialist at once too