Audio stops / interrupts and comes back after some seconds

I observed this issue before and it came back now.
I create a layer and made a simple sequencing.
So, it is just running in a loop and out of the blue the audio stops and starts after a few seconds again.
Sometimes it does it - sometimes it doesn’t.
Now I have also linked it via network to my Ableton live, so not the internal sequencer is playing, but Ableton playing midi tracks to the Zynthian midi channel and the same thing happens.
I know if I will reboot, the issue might not be there again, but at some point, it will show up again.
I observed this some weeks ago for the first time, die updates in between and today it is doing it again.

I have a very basic setup with a Pi4 8GB and an external audio card connected the NI Traktor Audio 2 MKII which works just fine.

I can’t figure out what causes these dropouts.

Link to a short video footage to demonstrate the issue:
Zynthian Audio Dropout video footage

It would be interesting to watch patchage during the incident to see if any audio routing changes.

I was wondering if the soundcard might drop out and come back.
So, if I reboot the Zynthian or also just reboot the UI, it is gone for some time and then comes back again.
I try the internal Pi audio card and see if the same happens with that one.
In case it is the sound card, would there be anything I can do? Maybe some adjustments in the audio card settings? I gonna add a screenshot of the settings.

Ok, the same dropout happens with the internal Pi4 audio card.

did you observe audio and MIDI routing during the incident? It will be good to iterate through the possible issues and eliminate them to hone in on the cause.

Could you explain please, how this is done?
How to observe audio and MIDI routing?
I guess there is a terminal command to watch the stream.

@riban …I am still having the problem and the fun is gone playing with the Zynthian.
I can’t figure out how to solve this.
It seems to be an issue of the software, if it happens with both (internal and external) sound cards.
You mentioned to observe the midi routing and audio routing.
there is no midi routing. It does it also with the internal sequencer and just one synth layer.
first it works for some time and then out of the blue it starts and keeps repeating.
Pi4 with 8GB RAM should not be an issue, software updated, nothing else connected.
only zynthian with mini jack in the internal Pi sound card.
Is that sound card not able to play one synth track? I cant believe it.

Some observations (but not resolutions yet):

  • In the video, when the sound stops, so does the indication of MIDI input
  • The audio level meters continue to behave as expected for a loss of audio hence Zynthian core continue to run
  • There is an xrun coincidental to return of audio

I suspect some odd routing issue, probably of the MIDI signal. How is the MIDI being driven?

@riban it happens also if I program a simple sequence in the sequencer, without any external midi input.
I will do another test today with only zynthinan on power, internal PI audio, by the use of headphone jack and will create one midi layer with a synth and a simple 4 bar sequence and let it run for some time.
when it happens, I will film it again.
in case it is happening this way again, what could be done?
Do you want me to attach screenshots of my configuration settings?

The external devices I usually connect are a USB mouse on the 2.0 port and a Korg Nano Keys 2 also on USB 2.0 and if I use the NI Traktor Audio 2 I plug it into the 3.0 port.
Mostly I also have the LAN cable connected to check the configuration settings and I also used Ableton to remote control all available 15 MIDI channels on the Zynthian for a test, which worked fine, but also caused such dropouts.

As I explained. The dropouts happen in all settings I did so far. Minimal setup with basically nothing connected and maximum setup with external sound card and Ableton remote controlling the MIDI channels.

This all works really nicely until the audio suddenly stops, just to come back after some moments.
Once this happens after some time of running it, it keeps happening in short periods over and over again and doesn’t go away. So, it does not happen from the start - only after some time of performing.