GM MIDI w/PC messages on testing/stable images

I am trying to get GM MIDI working using the Fluidsynth GM snapshot. When I load the GMR3 zss and play the midi test file I receive the first 2 PC messages. Ch1 PC is received and sets track 1, Ch2 PC is received and sets the remaining tracks to the patch of Ch2. The Ch10 track sets to percussion(I can hear the first note on) but then sets to PC received from Ch2.

I confirmed this watching the MIDI log. No difference if I turn off ZS3 PC capture. I checked the behaviour of my stable image and it is doing the same thing. GM PC messages not working properly. I’ve seen this work in the past when I first started with Zynthian but I haven’t been able to get this working for quite some time now.

I have a custom wired Zynthian but still use ttymidi. I don’t think my issue is hardware.

** Updated**
On Testing with ZS3 PC capture disabled, I setup a midi controller to send PC messages on each channel(16 knobs). I loaded the FluidGMR3 snapshot and selected a layer on the zynmixer. From the layer parameter screen I turn any knob on my controller and the selected layer receives the PC message and changes the patch regardless of what channel the PC message is being sent. If I start a SMF from the midi recorder I receive some PC messages but not all and of course now I know that the PC messages were being sent to all channels regardless of channel setup.

I also just noticed that ZS3 PC capture disable is not working, with ZS3 off and master channel set to none I still am sending PC messages to snapshots if I send message on Ch16??

Very weird behaviour, I’m used to GM devices loading SMF with PC changes set including the drum channel PC.
Any ideas?
Thanks in advance

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I’ve fixed this on testing and now it’s working, at less with the Take5 examples included on the SD image.

Regarding the stable branch, it should work, as AFAIK, the changes that provoke the issue have been committed recently. Anyway, could you test with a fresh stable SD image to see if it works? Going back from testing to stable is not possible at all.

Anyway, we are not so far from a new stable version and testing branch start to be quite usable now.


Ahhh! You should update (by hand) the GM snapshot. In the file included in the SD image, the modulation value for channel 2 is 74, causing strange artifacts. I’ve fixed it, setting it to 0.

002-FluidR3 GM.zss (41.5 KB)


That worked! Thanks again for such a prompt response. GM Midi working with the Zynmixer was my final issue to be resolved. Zynthian has now become viable option for my solo work on stage.

I run my TC Helicon Voicelive effect pedal output (Guitar&Vocal) to ADC L/R balanced inputs, load 2 audio gain layers on the zynmixer and 13 or 14 GM SF2 layers(depending if I want Midi Master channel 16). All my SMFs with my backup tracks are stored in the Zynthian and are called up in the Midi recorder. If I don’t like the patches called up by the GM spec I can just select that layer from the zynmixer and either use replace synth or just change the patch. I can then save those layers as specific snapshots. I’m excited to start rehearsing with this setup, I wasn’t able to use my SMFs without a bunch of work to fix the layers….but now with PC messages setting up the patches I should be good to go. Lack of Channel 16 available to use in GM is no big deal, rarely do I see SMFs use all 16 channels and if they do they are normally drum tracks that can be collapsed to Channel 10.

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Hi @somervid ! has ve you tried to disable the master channel from the webconf? :wink: