Not the .db file, but the directory it’s sitting in (/opt/var/mt-daapd).
If the “runas” user can’t create files in /opt/var/mt-daapd, that’s when you get the error described.
So check to see that /opt/var/mt-daapd is owned by the user that is the “runas”, and delete the songs.db file. Then start it and see where you get.
— Ron
p.s. you can check this interactively by doing “su guest”, then changing to /opt/var/mt-daapd and see if you can create a file.
slug:/# su guest
slug:/$ cd /opt/var/mt-daapd
slug:/opt/var/mt-daapd$ touch test.fil
slug:/opt/var/mt-daapd$
if that won’t work, then mt-daapd won’t work either.
— Ron