Share your experience!
Hi!
Suddenly, out of nowhere, without any obvious reasons, my phone started to enter camera-mode, focusing in and out, and taking pictures.
It does not matter if I use the phone, or it's lying on the table. If I'm using software, or not.
I slept an hour this afternoon, it had taken roughly 50 pictures during 25 minutes, 10 during one random minute, then 1 picture 5 minutes later, so it doesen't seem to be any system behind it.
In addition, the camera button is not functioning anymore.
So basicly, it seems like the function is used by some internal pieces, however, it overrides the button of the camera as I can't use it.
Any ideas what could cause this? I'm so lost, I don't know if something inside the phone is not functioning, or if it's a virus.
Try performing a system repair using PC Companion as this will often fix issues - This will factory reset your phone and erase all data so best to backup before you begin
Switch off your phone and unplug from Pc (Hold volume up and power for around 10 seconds)
Start PC Companion and select Support zone then Update my phone/tablet then in Blue Repair my phone/tablet and follow the on screen instructions - When prompted connect your phone still switched off holding volume down or back button - This should start the repair or reformat process
If you are using Windows 8/8.1 or a 64bit operating system then adjust the settings for PC Companion and run in compatibility mode and chose Windows 7 or XP
If that fails then I'm sorry to hear this but you would need to either return your device to the place of purchase or contact Xperia care and have your device inspected http://www.sonymobile.com/global-en/support/contact-us/
I had a similar problem but with the power button on Original Xperia Z, washed it with soap and that got water under the power button causing the device to lock, unlock, restart, power off randomly. I returned it to service center and got the button replaced on my own expense as it was obviously wrong to use soap on phone.
I have a feeling that your problem is physical, but try restting first.
I let it run out of power, and let it sit like that a few hours. The problem is gone now, though got a feeling it will come back as I tried turning it off without any progress.
Could be soap, came back from a holiday and thought I needed to clean it a bit extra.
Will try the solution mentioned if it comes back, thanks 
Uhm... I dont know. I cleaned my devices with soap but nothing happened. I did it many times. My tablet was underwater for over 50 mins in a soap water... Nothing happened. Do as thommo said, perform a software repair by pc companion. Also from the z and z3 the waterproof has gone up. The waterproof jack and the ip rating.