NAS library not shown on RP4 after reboot

Volumio Development Bug reports
1

On my RPI4, my NAS is usually not showing in the Music Library UI after a reboot with DRC plugin enabled.
In order to troubleshoot I tested with latest versions (2.714 and DRC plugin 1.4.3) on clean install and discovered the following:

  • RPI2 + DRC plugin enabled --> OK --> NAS is always shown after reboot
  • RPI4 + DRC plugin enabled --> NOT OK --> NAS is usually NOT shown after reboot (occasionally it does)
  • RPI4 + DRC plugin disabled --> OK --> NAS is always shown after reboot
  • /mnt/NAS is correctly mounted always
  • Booting with DRC disabled --> mpd process runs as user ‘mpd’ --> NAS visible
  • Booting with DRC enabled –> mpd process runs as user ‘root’ --> NAS not visible
  • After manually restarting MPD (sudo systemctl restart mpd) --> mpd process runs as user ‘mpd’ --> NAS visible

Could it be that after the plugin is started, MPD is restarted improperly (wrong user)
How can this be explained and fixed?

2

After delaying the startup of mpd: mpd is now running as user ‘mpd’ upon reboot and the NAS is now shown in the music library.
So there are clearly some ‘timing issues / race conditions’ in the startup of Volumio that becomes noticable on a RPI4.

I changed; /etc/systemd/system/multi-user.target.wants/mpd.service

[Service]
Type=notify
ExecStartPre=/bin/sleep 60
ExecStart=/usr/bin/mpd --no-daemon

But this is more a ‘workaround’ then a proper root cause solution