@tmchow
I have been encountering this issue either randomly or when I moved a vdisk for some time. This problem is usually not just related to hass on unraid but all vms. .
So far the only reliable fix for it that I have found is to create a new vm in the GUI with the same specs and add the existing hass vdisk to it.
This is fine for my hass vm but impacts my windows vm licenses.
I have also had some success with backup and restoring of the nvram but not enough to provide a reliable guide.