Huawei u8860 'not responding' errors?

hello to all,

i have Huawei u8860, it has hanging again and again and 'not responding' error for many applications is showing even i factory rest the phone. moreover, the sound is not coming from mobile even ringing or video etc.. any guidance? tips or tricks to resolve the prob? regards

other specifications are:

Model No.
u8860
Android version:
4.0.3
Baseband version:
404029
Kernel version
3.0.8-perf-00059-g3a757a2
android@localhost #1
Build number:
U8860IV100R001C00B923SP01