When browsing-by-artist this MP3-directory I again got the message “browse failed”. Then I reduced the number of songs, for testing, to 10 songs and then it works fine.
It looks like there has to be a limit which is exceeded.
My other music-library contains at this moment 10101 songs. This directory is 82 Gb, almost 9 Mb per song.
Probably timeout on waiting for browse data. You can try making an index on artist on the database — that should probably work.
foo@slug:~$ cd /opt/var/mt-daapd
foo@slug:/opt/var/mt-daapd$ sqlite songs.db
sqlite> create index idx_artist on songs(artist);
You’ll have to do that as root, probably, and then chown everything back to guest.
See what that does.