instance randomly rebooting and shutting down

instance id: i-d577494c

reboot system boot 3.13.0-165-gener Fri Jul 2 00:00 - 07:58 (07:58)
reboot system boot 3.13.0-165-gener Thu Jul 1 23:20 - 23:58 (00:38)
reboot system boot 3.13.0-165-gener Thu Jul 1 16:17 - 23:58 (07:41)
reboot system boot 3.13.0-165-gener Thu Jul 1 12:23 - 23:58 (11:34)
reboot system boot 3.13.0-165-gener Thu Jul 1 11:50 - 23:58 (12:08)

shutdown system down 3.13.0-165-gener Thu Jul 1 23:58 - 00:00 (00:01)
shutdown system down 3.13.0-165-gener Thu Jul 1 23:58 - 23:58 (00:00)

I got a notice a few weeks ago that this instance was being retired due to hardware degradation. I STOP'd/START'd to move to new hardware, a few times actually, but the problem continues. There has been no recent upgrades or updates, no new automated tasks added. I've looked through all the logs for clues but don't see anything.

Thank you for you reading and any assistance.