Blackberry curve 8320 camera, video player and standby mode button not work

It happened on my own mobile, BB curve 8320 but now I solved it out by doing soft reset, first I thought oh... need to upgrade its OS to new available version, in advantage getting new stuff on. In fact not like that, the solution only do Soft Reset or Master Reset (Wipe Handheld, doing this will lose all user data), so I decide to take in Soft Reset by only press Alt + right Shift + Del for seconds then it will reboot, and after rebooting few minutes, it's done!!!.