Also mir hats zumindest bei meinem TS-563 mit der alten Version 5.0.0.1891 den SSD Cache zerlegt. Hoffentlich ist das mit dem neuen Release erledigt.
Using SSD cache in earlier QTS 5.0.0 versions might cause data corruption issues. We have fixed all identified issues in this release. Important: If you discover suspicious symptoms on your device, DO NOT run a file system check in Storage & Snapshots. To learn more about the circumstances, impacts, and solutions, see our Technical Advisory: https://www.qnap.com/en/technical-advisory/tec-202112-01