Thank you for your speedy reply! I can still access the server with the dsub app (or substreamer). The database index on the server side also appears ok.
Could the connection be too slow? May I activate some additional buffering?
Yes, I’m planning to use Navidrome in the future (compiling it myself for the ARM7 architecture). Currently it’s a standard subsonic installation. I haven’t had any server issues before. As mentioned, dsub and substreamer work but these apps don’t require a local sync.