Use shairport-sync AirPlay with RPi-Jukebox-RFID

[JoernUhl]

Hi,

I hope it is correct that I am posting my question here as I am pretty sure it is actually not an issue with RPi-Jukebox-RFID but rather my own inability to make this work. Please let me know if this question should be asked elsewhere :-)

I installed shairport-sync along with RPi-Jukebox-RFID. I installed both on a Raspberry Pi 3, with an Adafruit Speaker Bonnet. If I use the functionality provided by RPi-Jukebox-RFID, I get sound and music plays as it should. However, if I try to use airplay from any of my iDevices, no sound is heard.

After running the command systemctl status shairport-sync I get the following output a couple of times:

 shairport-sync.service - Shairport Sync - AirPlay Audio Receiver
   Loaded: loaded (/lib/systemd/system/shairport-sync.service; enabled; vendor preset: enabled)
   Active: active (running) since Fri 2021-01-22 17:39:53 GMT; 30min ago
 Main PID: 480 (shairport-sync)
    Tasks: 11 (limit: 2063)
   CGroup: /system.slice/shairport-sync.service
           └─480 /usr/local/bin/shairport-sync

as well as:

warning: alsa: error -16 ("Device or resource busy") opening alsa device "hw:0".

Running aplay --list-devices, I get:

**** List of PLAYBACK Hardware Devices ****
card 0: sndrpihifiberry [snd_rpi_hifiberry_dac], device 0: HifiBerry DAC HiFi pcm5102a-hifi-0 [HifiBerry DAC HiFi pcm5102a-hifi-0]
  Subdevices: 0/1
  Subdevice #0: subdevice #0

In /etc/shairport-sync.conf I added within the alsa section:

output_device = "hw:0";

and

mixer_control_name = "Master";

I guess the RPi-Jukebox-RFID installation occupies the Adafruit Speaker Bonnet and is not letting shairport-sync play any music? I would appreciate any tipps or pointers into the right direction :-)

And again, sorry if I am posting this question in the wrong forum.

Thanks a lot for your help,

jrn

[s-martin]

@ChisSoc can you help here?

[ghost]

I had a similar issue in another context. And indeed, ALSA resources are exclusive to a single process using them. With mpc, it takes hold of the Alsa ressource when playing music or when pausing. When you do a proper stop with mpc stop, the Alsa ressource is released and another process can use them. Check with mpc status which state mpc is in.

For me that was good enough. I did no investigate further how to configure Alsa to mix together multiple streams. It should be possible with the dmix plug. Hit your favorite search enginge with alsa mixer two streams or similar. Good luck!

[jrnhl]

Hi @ChisSoc,

Thank you very much for your reply.

Once I play some music using RPi-Jukebox-RFID and run this command mpc status, I receive this output:

Some Artist - Some Song
[playing] #1/1   0:00/0:00 (0%)
volume: 15%   repeat: off   random: off   single: off   consume: off

When I run mpc stop followed by mpc status I receive this output: volume: 15% repeat: off random: off single: off consume: off

However, at all times I am receiving this error running systemctl status shairport-sync: warning: alsa: error -16 ("Device or resource busy") opening alsa device "hw:0".

I also tried to add the following to my .asoundrc file to allow for multiple streams:

pcm.!default {
              type plug
              slave.pcm "dmixer"
}
pcm.dmixer  {
            type dmix
        ipc_key 1024
        slave {
          pcm "hw:1,0"
          period_time 0
              period_size 1024
          buffer_size 4096
          rate 44100
        }
        bindings {
          0 0
          1 1
        }
}
ctl.dmixer {
       type hw
       card 0
}

Unfortunately with the same error messages as stated above.

Do you have any other idea what I could try? I appreciate all your help! Thank you very much :-)

[ghost]

Looking at your /etc/shairport-sync.conf, I'd it is likely this is the culprit. You are trying to use the hardware card directly instead of any of your Alsa devices. You will need to setup both, shariport and mpd, to use the dmixer as device.

First try playing sound with aplay -D dmixer /usr/share/sounds/alsa/Front_Center.wav to ensure your asound is correctly set up. Then try playing multiple files at once from different consoles.

Then check your mpd.conf. You might find the issue helpful #1198 for the mpd.conf options.