Phone randomly reboots

[Wvg]

Hello,

The past half year i've been having some problems with my xperia play R800i. At completely random times it will reboot. Mostly 1 second after I press the home button to unlock it and it happens when i'm listening to music, checking my email, checking 9gag or when i'm not using the phone at all, in the middle of the night (etc, etc). I also noticed that the battery loses a great deal of % whenever that happens.

So I bought A new battery but that did not fix it. I figured out that it only happens when I have wifi turned on, if it's off it will work flawlessly. 

The phone will log on to a lot of networks during my day. I have my home network, free wifi hotspots, my work and in the train. (whenever i walk throught the trainstation the phone will connect and disconnect a lot of times in a row, because all trains have separete wifi routers.)

I have reinstalled the latest version via pc compagnion, but that did not help. the only thing that works is to keep wifi turned off at all times.

How can this be fixed?

thanks in advance

[Alexander1]

You could try to use the phone without any SIM card or SD card to see if that works better. 

You can also try to start the phone in safe mode to see if the problem may be related to any 3rd party app installed in the phone: 

http://talk.sonymobile.com/t5/FAQ/How-to-boot-your-phone-into-safe-mode/m-p/348008#U348008

If the problem still persists, you should have your phone examined at a service center. Please contact your local Xperia support team for more information: 

http://www.sonymobile.com/global-en/support/contact-us/