minidlna config and logs

You use journalctl to see logs from ssh.  If you have trouble with that, then perhaps try downloading the log zip file from the web ui, and look at the log in there.

You could also try a binary search process.  That is, move all the files out of Music, and confirm that the scan completes.  Then move half of the files back, and then scan again.  If that succeeds, then move half the remaining folders back into Music.  If it fails, then move out half the files currently in Music (keeping them separated from the rest).  Though tedious, that process will zero in on the file(s) that cause the scan to fail.