HTC Mobile Model No :p3300 — sound settings are automatically get dysfunction

hello,

this is to inform that my htc mobile phone P3300 is not functioning normally, the sound settings get automatically change for example, the side button of increase/decrease volume button get started operating automatically and create a very irritating sound.

secondly it create music files of its own continously and which lead to disk space full issue. i dont know what happen to it, even i am not getting proper service center contact to show the mobile. request you to guide me . i didnt find such issues with my previous mobile phone from nokia and sony .

regards
Sandeep