Share your experience!
I would say that the problem has to do with your previous issue (water damage)
http://talk.sonymobile.com/t5/Xperia-Z1-Z1s/Water-got-inside-my-Z1/m-p/734985#M28574
You should stop by your local Xperia Care
http://www.sonymobile.com/global-en/support/contact-us/