Hi,
strange behaviour indeed, what about the following ideas:
'Changes Locked'. Modification are not allowed at current state '- sounds somehow logical: is there any background-process running? Yes - try to stop it or give it time to end; no:
- switch off the HIFIDELIO, pull the power-plug, pull out the LAN-Cable and all other peripheral connections, power-on again (with the cd-eject-button pressed if there is a cd locked in the drive to force an cd-eject);
- change of behaviour? Yes: try database-check; no: switch off, pull the power-plug, open the cover and check all connections/connectors to the power-supply, to the drives, to the main-board, to the display etc. (bad connections to the drives often seemed to be the cause of such kind of trouble, or the hdd itself, you seem to have an older one?). Reseat everything, close the cover + try again, what happend?
Have you done any Linux or Telnet-operations on the machine? In the HIFIDELIO-menu switch off all these services + try again?
Maybe there are some more support-ideas from other forum-members here; and, btw, if the machine is somehow working again, try to draw a backup of your music-files (which fore sure you did already

).
Wish you success, pls. post the outcome here.
Greetings from Hamburg, Michael