What I am trying to achieve
I am trying to set up Zynthian emulator (i do not have any hardware parts) to work under Raspberry Pi 3b.
I want to use Zynthian emulator in a "poor man's build" via VNC in the end , replacing TFT screen and knobs with my tablet over wifi, as unfortunately I do not have spare money, but i have spare 6.5'' tablet instead and a USB CM108 audiocard, which had a fine (latency too) for me when I tried SamplerBox under Raspbian.
Probably I will be able to switch to HiFiBerry later, if sound quality/latency issues will be the last thing left.
What I have done:
0) I had started with Gorgona image flashed.
1)I had replaced /dev/fb1 with /dev/fb0 everywhere where I found it to be mentioned (in zynthian scripts and Xorg config), commented out TFT screen driver line in /boot/config.txt to replace unexisting TFT screen with HDMI display.
1)I had commented out hifiberry driver line in /boot/config.txt, and was able to force Zynthian to work with my usb CM108 audiocard by setting a proper device (hw:device,0) in jackd2 service file and zynthian_emu.sh script
3) I had installed python3-PyQt4 package from the default repository (zynthian emu gui requires it to start, but it was not initially included), replaced zynthian.sh with zynthian_emu.sh in systemd service file.
4) created a file with "PROTOTYPE-EMU'" text in /zynthian/zynthian_hw_version.txt, and replaced prototype variable with PROTOTYPE-EMU in zynthian_gui_config.py
5) added max_usb_current=1 in a /boot/config.txt to ensure that keyboard, usb audio, mouse, and a USB MIDI keyboard will not jump out of the power consumption limit.
1) Zynthian GUI (A window where presets can be choosen) appears, and seems to respond correctly to mouse clicks
2) Zynthian Emulator (that window with knobs and buttons) appears around/under GUI too and looks fine.
3) After choosing a preset sound starts playing with a latency fine for me.
1) Any manupulations with Zynthian Emulator knobs or buttons lead to disappearing of Zynthian GUI window.
zynthian_gui.sh dissappears from ps -axu list too.(If started manualy instead of service, from the xterm in the window manager environment, Zynthian Emulator console starts complaining that no process pid exist. Also, emulator has a separate window in the window manager env, so i was able to check that GUI is not just "sent to back")
Sound does not disappear when GUI dies.
2) Sound disappears after about couple of minutes (3m12second according to last measurement) of playing, regardless of GUI issue , increasing jackd -p parameter up to 1024 does not have any effect. No glitches typical for latency problems are heard before or in the moment of disappearing sound.
1) Does anyone have any up-to-date instructions for such case?
For setting up zynthian emulator correctly (and sharing it via vnc, if possible, but the vnc part seems to be exotic offtopic, so I think I will have to deal with it on my own )
Existing manuals that I could find seem to be outdated and lack details.
2) How can I get any zynthian extended logs to read and think about? Looks like I am completely out of ideas at his point and no new information to debug and move forward.
3) What can I possibly do with Zynthian Emu killing Zynthian GUI?
4) Any ideas regarding disappearing sound?
P.S. I've tried to make the same starting with bare Raspbian Jessie image (the one with desktop environment), and runned into the same GUI dying issue after installation and +- the same tuning.
Would like to notice, that this kind of setup fails on the compilation stage due to running out of memory (regardless of swtching to init 3 and disabling xserver), so i had to add 300mb of swap and disable swap tuning in setup script to give it a chance to finish the job,