Share your experience!
I have tried replacing xperia default keyboard with google keyboard but the issue still exist.
Solved! Go to Solution.
What if you boot on safe mode?
http://talk.sonymobile.com/t5/FAQ/How-to-boot-your-phone-into-safe-mode/m-p/348008#U348008
In safe mode it works fine. that means a 3rd party app is interfering.. How could I search and shot it down?
Trial and error, it could be a third party messaging app, antivirus, taskiller, keyboard app, etc.