The only thing I can think of is, in terms of DietPi’s end:
- DietPi has a RAMdisk for all its settings and configurations. If the system is hard rebooted, the RAMdisk does not save to disk, resulting in the next boot reverting back to a previous state.
However, once the software is installed, DietPi will reboot the system. So any changes made during dietpi-software installs, should not be affected.
It may be that the Roon Server application did not save the database/settings correctly, maybe it also loads into RAM and saves on process termination, however, unsure, would need a Roon dev to verify.
Either way, just verify the Roon Server service:
Aside from the service above and setting up the data locations, I believe the location must be manually setup in Roon Server during initial run.