Phone turns off by itself
I'm having an issue with my Nexus 4, Android 4.4, clean, not modded, no custom roms, no root.
There are two issues:
1. When the phone is charging at night, sometimes the phone turns off. To turn it on I need to press power+volume down, then recovery screen appears and I press the power to power the phone on.
2. When idle (at a desk, not used) the phone turns it self off. To turn it on I need to press power+volume down, hold it, connect to charger, red led starts flashing, battery icon appears and then the phone boots.
In both cases the phone have battery (usually is even more than 50%). My phone wears bumper.
Any help please! I already came late few times to work because of this