FreeNAS disks forget their assigned pool

On a regular basis (every 10 days or so) when I log into the UI, the dashboard does not show up.

When this happens I check Storage > Disks, and none of the disks on my machine have their pool assignments anymore.

All of the disks are set to 'always on' and advanced power management is Disabled.

Please help me diagnose why this occurs.

I am using Version:   FreeNAS-11.3-U3.1 on a dell T320 

Intel(R) Xeon(R) CPU E5-2407 0 @ 2.20GHz