I have experienced random crashes and reboots of the Phone ever since I put 8.1U on my 920. I was surprised to see my phone turned off a couple of times (had enough battery juice so that wasn't a factor) where the phone just turned itself off. I have also seen it just cold reboot when on my desk while I wasn't even using it.
In total I have counted about 7-8 instances of reboots/power offs in last 4-5 days. Anyone else? I have had probably 1-2 crashes on it ever since I bought it so this is shocking to me.
Sorry, everything works fine here. Maybe the battery is dying?