Share your experience!
The problem might be hardware related, things to test
settings > about phone > diagnoticst > test the phone
also, does your phone has a protective case or film?
Check if you experience the same while on safe mode
you could repair the phone with PCC
@alexdon has created a guide > software repair using PC Companion
Bridge (for Mac)
Alternatives on How to backup Xperias
http://talk.sonymobile.com/thread/36355
Hi spacelights,
In the worst case scenario you can also contact Sony Mobile within your region for further support. Use my signature to find these details.