Problems with snapserver/snapclient

[ccaper]

I'm not sure if this is a bug, as I'm very new to trying the snapcast feature (but having been using rAudio for 6 months now, just got a 2nd rPi set up with rAudio, and now trying the snapcast feature). Apologies if this is user error. I am very baffled though.

I have 2 rPi 4's, both of them have the HiFiBerry Digi2Pro hat in them for digital out. Both of them are on rAudio version 20231216.

I enabled the the snapserver on one of them (named rAudio-HiFi).
The output of the snapserver after enabling is:

snapcast 0.27.0-1
# cat /etc/default/snapserver
START_SNAPSERVER=true
SNAPSERVER_OPTS=""

snapserver.service- Snapcast server
     Loaded: loaded (/usr/lib/systemd/system/snapserver.service; enabled; preset: disabled)
     Active: active (running) since Fri 2024-01-05 16:58:11 CST; 4min 3s ago
       Docs: man:snapserver(1)
   Main PID: 394 (snapserver)
      Tasks: 5 (limit: 9289)
        CPU: 1.382s
     CGroup: /system.slice/snapserver.service
             └─394 /usr/bin/snapserver --logging.sink=system --server.datadir=/var/lib/snapserver

Jan 05 16:58:12 rAudio-hifi snapserver[394]: PcmStream: default, sampleFormat: 48000:16:2
Jan 05 16:58:12 rAudio-hifi snapserver[394]: PipeStream mode: create
Jan 05 16:58:12 rAudio-hifi snapserver[394]: Stream: {"fragment":"","host":"","path":"/tmp/snapfifo","query":{"chunk_ms":"20","codec":"flac","name":"default","sampleformat":"48000:16:2"},"raw":"pipe:////tmp/snapfifo?chunk_ms=20&codec=flac&name=default&sampleformat=48000:16:2","scheme":"pipe"}
Jan 05 16:58:12 rAudio-hifi snapserver[394]: Init - compression level: 2
Jan 05 16:58:12 rAudio-hifi snapserver[394]: Exception: end of file
Jan 05 16:58:12 rAudio-hifi snapserver[394]: Creating TCP acceptor for address: 0.0.0.0, port: 1705
Jan 05 16:58:12 rAudio-hifi snapserver[394]: Creating HTTP acceptor for address: 0.0.0.0, port: 1780
Jan 05 16:58:12 rAudio-hifi snapserver[394]: Creating stream acceptor for address: 0.0.0.0, port: 1704
Jan 05 16:58:12 rAudio-hifi snapserver[394]: Number of threads: 4, hw threads: 4
Jan 05 16:58:13 rAudio-hifi snapserver[394]: Service 'Snapcast' successfully established.

I then select an album to add to my playlist, and play it.

The output from the snapserver rAudio's MPD is:

mpd 0.23.14-2
# /srv/http/data/mpdconf/mpd.conf
# file - plug and play content  
# link                          
bind_to_address                 "0.0.0.0"
db_file                         "/srv/http/data/mpd/mpd.db"
music_directory                 "/mnt/MPD"
playlist_directory              "/srv/http/data/playlists"
state_file                      "/var/lib/mpd/mpdstate"
user                            "mpd"
input {
	plugin  "curl"
}
audio_output {
	name    "SnapServer"
	type    "snapcast"
	port    "1704"
	format  "48000:16:2"
}
audio_output {
	name           "hifiberry-digi"
	device         "hw:0,0"
	type           "alsa"
	auto_resample  "no"
	auto_format    "no"
	mixer_type     "none"
}

mpd.service- Music Player Daemon
     Loaded: loaded (/usr/lib/systemd/system/mpd.service; disabled; preset: disabled)
    Drop-In: /usr/lib/systemd/system/mpd.service.d
             └─00-arch.conf
             /etc/systemd/system/mpd.service.d
             └─override.conf
     Active: active (running) since Fri 2024-01-05 16:58:39 CST; 17min ago
       Docs: man:mpd(1)
             man:mpd.conf(5)
   Main PID: 767 (mpd)
      Tasks: 8 (limit: 9289)
        CPU: 5.763s
     CGroup: /system.slice/mpd.service
             └─767 /usr/bin/mpd --systemd /srv/http/data/mpdconf/mpd.conf

Jan 05 16:58:37 rAudio-hifi systemd[1]: Starting Music Player Daemon...
Jan 05 16:58:39 rAudio-hifi systemd[1]: Started Music Player Daemon.
Jan 05 17:02:53 rAudio-hifi mpd[767]: exception: Failed to enable output "SnapServer" (snapcast); Failed to bind to '0.0.0.0:1704'; Failed to bind socket: Address already in use
Jan 05 17:05:37 rAudio-hifi mpd[767]: player: played "NAS/Router/FLAC/The Smiths/Strangeways, Here We Come/The Smiths - Strangeways, Here We Come -07- Unhappy Birthday.flac"
Jan 05 17:05:37 rAudio-hifi mpd[767]: exception: Failed to enable output "SnapServer" (snapcast); Failed to bind to '0.0.0.0:1704'; Failed to bind socket: Address already in use
Jan 05 17:11:13 rAudio-hifi mpd[767]: player: played "NAS/Router/FLAC/The Smiths/Strangeways, Here We Come/The Smiths - Strangeways, Here We Come -08- Paint A Vulgar Picture.flac"
Jan 05 17:11:13 rAudio-hifi mpd[767]: exception: Failed to enable output "SnapServer" (snapcast); Failed to bind to '0.0.0.0:1704'; Failed to bind socket: Address already in use
Jan 05 17:13:15 rAudio-hifi mpd[767]: player: played "NAS/Router/FLAC/The Smiths/Strangeways, Here We Come/The Smiths - Strangeways, Here We Come -09- Death At One’s Elbow.flac"
Jan 05 17:13:15 rAudio-hifi mpd[767]: exception: Failed to enable output "SnapServer" (snapcast); Failed to bind to '0.0.0.0:1704'; Failed to bind socket: Address already in use

I then go to the 2nd rAudio device (named rAudio-tv), and enable the snapclient.

I then go the the Networks under config icon, and add the snapserver.

I see the snapclient rAudio player show the metadata for the song I'm playing, it is correct and it updates. But I hear no audio.

The output from the snapclient is:

snapcast 0.27.0-1
# cat /etc/default/snapclient
SNAPCLIENT_OPTS="--latency=800"

snapclient.service- Snapcast client
     Loaded: loaded (/usr/lib/systemd/system/snapclient.service; disabled; preset: disabled)
     Active: active (running) since Fri 2024-01-05 17:03:48 CST; 15min ago
       Docs: man:snapclient(1)
   Main PID: 1393 (snapclient)
      Tasks: 2 (limit: 9289)
        CPU: 1.173s
     CGroup: /system.slice/snapclient.service
             └─1393 /usr/bin/snapclient --logsink=system --latency=800

Jan 05 17:03:48 rAudio-tv snapclient[1393]: Sampleformat: 48000:16:2, stream: 48000:16:2
Jan 05 17:03:48 rAudio-tv snapclient[1393]: Using default buffer_time: 80 ms, default fragments: 4
Jan 05 17:03:48 rAudio-tv snapclient[1393]: Exception: Can't open default:CARD=sndrpihifiberry, error: Device or resource busy, code: -16
Jan 05 17:03:48 rAudio-tv snapclient[1393]: Exception in initAlsa: Can't open default:CARD=sndrpihifiberry, error: Device or resource busy
Jan 05 17:03:48 rAudio-tv snapclient[1393]: Exception in initAlsa: Can't open default:CARD=sndrpihifiberry, error: Device or resource busy
Jan 05 17:03:48 rAudio-tv snapclient[1393]: diff to server [ms]: 5976.2
Jan 05 17:03:48 rAudio-tv snapclient[1393]: PCM name: default:CARD=sndrpihifiberry, sample rate: 48000 Hz, channels: 2, buffer time: 80000 us, periods: 4, period time: 20000 us, period frames: 960
Jan 05 17:03:48 rAudio-tv snapclient[1393]: No chunks available
Jan 05 17:03:48 rAudio-tv snapclient[1393]: Failed to get chunk
Jan 05 17:03:53 rAudio-tv snapclient[1393]: No chunk received for 5000ms. Closing ALSA.

After connecting the snapclient rAudio to the snapserver, I go back to the snapserver rAudio and look at the snapserver logs, and I see the new lines added:

Jan 05 17:03:48 rAudio-hifi snapserver[394]: StreamServer::NewConnection: 192.168.5.121
Jan 05 17:03:48 rAudio-hifi snapserver[394]: StreamServer::NewConnection: 192.168.5.121
Jan 05 17:03:48 rAudio-hifi snapserver[394]: Hello from d8:3a:dd:90:75:d8, host: rAudio-tv, v0.27.0, ClientName: Snapclient, OS: Arch Linux ARM, Arch: aarch64, Protocol version: 2
Jan 05 17:03:48 rAudio-hifi snapserver[394]: Hello from d8:3a:dd:90:75:d8, host: rAudio-tv, v0.27.0, ClientName: Snapclient, OS: Arch Linux ARM, Arch: aarch64, Protocol version: 2
Jan 05 17:03:48 rAudio-hifi snapserver[394]: Error reading message header of length 0: End of file
Jan 05 17:03:48 rAudio-hifi snapserver[394]: onDisconnect: d8:3a:dd:90:75:d8
Jan 05 17:03:48 rAudio-hifi snapserver[394]: Error in socket shutdown: Transport endpoint is not connected

So this shows the client connect to the server, and that IP is the IP of my snapclient rAudio.

I also installed the Snapcast app on my android phone, and see the snapserver, but it plays no audio. This makes me think my problem lies in my snapserver, and I see errors in the log files show above. But I also see errors in the snapclient. So very baffled.

The snapserver logs is showing some errors that are of interest to me:

Jan 05 17:05:37 rAudio-hifi mpd[767]: exception: Failed to enable output "SnapServer" (snapcast); Failed to bind to '0.0.0.0:1704'; Failed to bind socket: Address already in use

I have also swapped which rAudio is the snapserver and the snapclient, and met the same results. So this is not unique to one of my rAudio devices (but both are the same rPi, same rAudio version, same HiFiBerry hat, same settings).

I did try the streamer for browsers, MPD httpd, and that worked just fine. It's just the snapcast that isn't working and I am very baffled. Any insight? This is a feature on the rAudio I was really hoping to use.

Thank you very much in advance for any insight.