Hello jaisingh,
there may be a possibility that the unit is defective. Have you tried to factory restore this yet?
I suggest you contact your Polycom reseller as he can advise you on the options you would have in regards contacting Polycom support and / or a RMA of the unit.
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
Best Regards
Steffen Baier
Polycom Global Services