I've only had this 520 for 3 days, it too is powering off and rebooting randomly. I've been doing some investigations at this end. Currently at work, the phone is plugged into the computer via USB and sat on the desk (i.e. no movement or vibration). the battery is fully charged. I have . 'pinched' the terminals on the battery together for a tighter fit, and wedged folded paper up under the battery and even tried roughing the phone up a bit to test for loose battery connections.
If I switch the wifi on, it does a search and connects to an available network here which on this phone seems to be 'the cloud'. Once connected it powers off within seconds.... it's on and off like a yo yo. I'm constantly seeing little sync windows pop up on the laptop. If I turn wifi 'off'... it sits there quite happily for hours (like it has done this morning, and the last 15 minutes since last disabling wifi.
Not sure if this is of any use to anyone, but that's what's going on at this end.
Anyone got any ideas on this test ? I'm curious about the 512Mb RAM comment above but don't know enough about IT to understand the relation between that and memory drains when connecting to wifi.
I've not tested this phone elsewhere or on other wifi networks.
I installed all available updates yesterday morning (21/2/14). Can't say whether the problem existed prior t this as I only brought the phone into this building at work yesterday. I do know that it was fine on the day I bought it (the day before) but I was on the road for most of the time using the sat nav with plenty of vibration in the car and no tweaks to the battery area as listed above (done yesterday afternoon)
It was fine at home last night too other than resetting the time by about 5 hours. I'm on the verge of taking it back to the store.
No apps installed other than Here Drive to replace the 'beta' version that came with the phone.
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