Curious; will it reboot (immediately) after it shuts down? Does it then crash, or stay up for a couple hours and do the repeat..?
Is it hot to the touch..? Any battery readings to note, for time remaining/capacity left?
Wondering if it's collapsing, or sleep mode, or ...? always at the same time in?
The monitoring software makes sense, as I watched that for a PC that would overheat and could watch the temps rise...