jawn
November 11, 2025, 10:52am
1
opened 12:58PM - 10 Nov 25 UTC
# Describe the issue
When (cold) booting or rebooting, the Zynthian often stops … with the boot screen "Audio/MIDI" error.
The zynthian service status log ends with:
> Nov 10 09:47:46 pi5 startx[2840]: JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
> Nov 10 09:47:46 pi5 startx[2840]: ZynMidiRouter: Error connecting with jack server.
> Nov 10 09:47:46 pi5 startx[2840]: ERROR:zynthian_gui_config.<module>: lib_zyncore: Failed to initialise zynmidirouter (2)
> Nov 10 09:47:46 pi5 startx[1019]: *******************
> Nov 10 09:47:46 pi5 startx[1019]: EXIT STATUS => 202
## Additional information
The Pi is powered via an official Raspberry Pi Power Supply. When the Pi boots successfully, the audio interface is working as expected and seems to remain stable. Note the error mentions the zynmidirouter but the configuration has no physical MIDI connections nor MIDI devices connected.
I reflashed a second MicroSD card to make sure this is not related to the card - same result.
After using Main > Remove all, I was also able to reproduce the issue within 2 or 3 reboots.
# To Reproduce
## Steps to reproduce the behavior:
1. Cold boot the Zynthian
- or push the restart button on Pi5
- or restart from the GUI
**Issue occurs frequently, but not each time.**
## Expected behaviour
Zynthian boots successfully and ready to use.
## Actual behaviour
<img width="993" height="706" alt="Image" src="https://github.com/user-attachments/assets/54aeeace-0aee-44fa-8637-5baf327716e4" />
(venv) root@pi5:~# systemctl status zynthian > log.txt
(venv) root@pi5:~# cat log.txt
● zynthian.service - Zynthian User Interface
Loaded: loaded (/etc/systemd/system/zynthian.service; enabled; preset: enabled)
Active: active (running) since Mon 2025-11-10 09:43:58 CET; 3min 53s ago
Main PID: 783 (startx)
Tasks: 6 (limit: 9579)
CPU: 14.129s
CGroup: /system.slice/zynthian.service
├─ 783 /bin/sh /usr/bin/startx ./zynthian.sh -- -r -s 0
├─ 912 xinit ./zynthian.sh -- /usr/bin/X :0 -r -s 0 -auth /tmp/serverauth.dUa4BV1QkB
├─ 913 /usr/lib/xorg/Xorg :0 -r -s 0 -auth /tmp/serverauth.dUa4BV1QkB
├─1019 /bin/bash ./zynthian.sh
└─2866 sleep 10
Nov 10 09:47:46 pi5 startx[2840]: JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
Nov 10 09:47:46 pi5 startx[2840]: ZynMidiRouter: Error connecting with jack server.
Nov 10 09:47:46 pi5 startx[2840]: ERROR:zynthian_gui_config.<module>: lib_zyncore: Failed to initialise zynmidirouter (2)
Nov 10 09:47:46 pi5 startx[1019]: *******************
Nov 10 09:47:46 pi5 startx[1019]: EXIT STATUS => 202
Nov 10 09:47:46 pi5 startx[1019]: *******************
Nov 10 09:47:46 pi5 startx[2857]: /zynthian/config/img/fb_zynthian_message.jpg is a 800x480 JPEG image, color space YCbCr, 3 comps, Huffman coding.
Nov 10 09:47:46 pi5 startx[2857]: Zooming image by 100%...done
Nov 10 09:47:46 pi5 startx[2857]: Merging...done
Nov 10 09:47:46 pi5 startx[2857]: Building XImage...done
# Screenshots
If applicable, add screenshots to help explain your problem.
# Additional context
Add any other context about the problem here.
# Configuration
Summary:
- Custom Pi 5 with touch display
- Audio interface is USB hotplugged Shure MV51
- Fresh MicroSD card: fresh stable oram image (2025-11-05-zynthianos-oram-2511-stable.img.xz), switched to staging (oram) via webconf, then updates applied via regular UI.
zynmidirouter
## Hardware
```
Raspberry Pi 5 Model B Rev 1.1
Audio: Default
Display: MIPI DSI 800x480
Wiring: TOUCH_ONLY
I2C: Not detected
Profile: v5
```
## System
```
Debian GNU/Linux 12 (bookworm)
Build Date: 2025-11-05
Memory: 9% (754M/8063M)
Internal Storage: 7% (16G/235G ext4)
Temperature: 47.7ºC
Overclock: None
```
## MIDI & UI
```
Tuning: 440 Hz
Master Channel: Off
Preload Presets: On
ZS3 (SubSnapShots): On
Power Save: 10 minutes
Audio Levels on Snapshots: On
```
## Software
```
zyncoder: oram (e4c91c4)
zynthian-ui: oram (b4a605b)
zynthian-sys: oram (8c25073)
zynthian-data: oram (e4e24b8)
zynthian-webconf: oram (f851967)
```
Hi,
I logged this issue following the recent oram stable image and updating to oram staging.
Any advice on additional troubleshooting steps?
Did you see @riban ‘s post in github re “You need a core audio device”?
I don’t understand what
Audio interface is USB hotplugged Shure MV51
means. Do you mean you are trying to boot without any audio interface device plugged in? Or is there always the MV51? Either way I would not expect it to work, so the question becomes why does it sometimes work, and I don’t know the answer. But a possible work around would be to get an inexpensive USB audio interface such as a Behringer UCA202 to satisfy jackd’s requirement for an audio device, and then hotplug the MV51.
jawn
November 11, 2025, 7:19pm
3
Thanks for your quick replies @riban and @tunagenes !
I stupidly forgot to specify this USB mike as an audio device when starting from a fresh microsd. I added the details in the issue on github. The issue seems to be fixed for now, though it will take longer to be really sure.
I understand and appreciate the recommendation for regular audio device, and am also playing with those occasionally (one of Pisound, Zoom R8 and hifiberry dad+ pro). This Shure microphone works surprisingly well and its audio out works for headphone practice, including as output for Zynthian.
However the goal of this lightweight pi 5 plus 5 inch touch screen plus usb Mike combo is to act as a lightweight and mobile setup.
1 Like
That’s great, who would have thunk it, a microphone with audio output!
1 Like