This is a continuation to the issue I wanted to solved in this topic. It just went to different places so I though I will open a new topic to this problem I'm facing.

I have a pd patch that doing some audio playback reading some files from buffer. I'm running it on my Pi4.

I wanted it to start on boot every time and to be able to reset itself if crashing for some reason.
I was suggested to use that service script:

[Unit]
Description=My PureData service

[Service]
Type=simple
LimitNOFILE=1000000
ExecStart=/usr/bin/puredata -nogui  -open /home/pi/mypatch.pd
WorkingDirectory=/home/pi
User=pi
Group=pi
Restart=always
# Restart service after 10 seconds if service crashes
RestartSec=10

[Install]
WantedBy=multi-user.target

The above was working great using the built in 3.5mm audio jack.
I then bought UGREEN USB audio interface as I was facing with some poor audio quality at the output.

I set the audio preference in PD to choose the USB Audio Interface as the output.

When I boot the Pi I'm getting this error from the service (see picture)

If I'm typing sudo systemctl restart my_puredata.service the PD patch is back to work just fine. No Alsa error, but on the initial boot it is not working.

Any idea why this happen when using the USB AudioInterface? anything I can do in order to make it work?

So If to conclude:

When I start the same pd patch using the same service script but without a USB audio interface is working just fine.

When I start the same pd patch with the USB audio interface but using the autostart file:

sudo nano /etc/xdg/lxsession/LXDE-pi/autostart

Is also working just fine.

But the combination of the USB audio interface and the service script is just not working.

Thanks for any help.

The USB device is maybe not yet available when your service start.
Try to add alsa as a requirement

[Unit]
Description=My PureData service

[Service]
Type=simple
LimitNOFILE=1000000
ExecStart=/usr/bin/puredata -nogui  -open /home/pi/mypatch.pd
WorkingDirectory=/home/pi
User=pi
Group=pi
Restart=always
# Restart service after 10 seconds if service crashes
RestartSec=10
# Alsa must have restored cards state
Requires=alsa-restore.service

[Install]
WantedBy=multi-user.target

thanks but this did not help. I notice someting interesting - when reboot pi the pd patch will start just fine, When shouting down Pi then boot, the pd patch will fail to start (also error message)
Is this a clue to understand the issue I'm facing ?

I was thinking to write a script that running the line:
" sudo systemctl restart my_puredata.service "after 5 seconds after booting. What do you think about this solution?
Thanks

I Write a cron script that restart pd service on boot after 6 seconds.

Now I'm getting the following error at the pd service: Alsa output Error (snd_pcm_open): Device or resource busy

@KMETE Ifyou are using a [loadbang] in your patch to start DSP ... i.e. [; pd dsp 1( then try delaying the loadbang with e.g. [delay 2000] between the two.
David.

@whale-av This is exactly what I did and still not work...

@KMETE Another couple of possibilities........
https://forum.pdpatchrepo.info/topic/7655/alsa-output-error-snd-_pcm-_open-device-or-resource-busy
https://forum.pdpatchrepo.info/topic/11146/ubuntu-browsers-and-puredata-wont-share-audio-output-device-solved
David.

@whale-av said:

https://forum.pdpatchrepo.info/topic/11146/ubuntu-browsers-and-puredata-wont-share-audio-output-device-solved

I have seen the first link. do I also want to at pulse ? or I should configure it to my USB Audio Interface?

@KMETE It is many years since I set up my RPI... and I remember different problems with an RPI2 and an RPI3B with different Linux flavours.... it can be complicated.
I wonder whether you should move the ExecStart to the end of the script so that everything else is done before you start the patch and Pd.
But more likely is the audio group setting....... https://forum.pdpatchrepo.info/topic/11146/ubuntu-browsers-and-puredata-wont-share-audio-output-device-solved/7
David.

Thanks. I did not manage to fix it.
I will just auto open the patch via

sudo nano /etc/xdg/lxsession/LXDE-pi/autostart

Maybe adding the command sleep 7 to the pd service file will help?
can I just insert sleep 6 at the top of that script?

I Think I solved it!! I have added that line:

ExecStartPre=/bin/sleep 7 

at the beginning of the [Service] and it seems to work!

although patch is working, I'm still getting those two errors:

Is it something to worry about?

I run again my puredata service after reinstalling my pi os.

Im getting this message:

What is:

Watchdog: signaling pd... 

something to worry about?

and if I'm already writing regarding the pure data service. in a case that the patch is working but for some reason the usb audio interface is stopped working. Is there anyway to make pd restarting?