Follow up to my post from earlier today. My NUC SSD did not fail. Downloaded the latest Roon OS and installed it via USB stick boot. Solved the problem. FYI, did this very same thing earlier today and it did not solve the problem. Roon must have pushed out a fix to the OS sometime after my first try. If you are having this problem with a NUC8, boot from the USB stick that has been flashed with the new OS and select REPAIR an install option when it boots.
A post was merged into an existing topic: Transcend 256GB SSD failed? [resolved]