I have a Zynthian V3 with an old software image (Gorgona?) I updates the software last week, and now the sustain pedal (sending midi-cc 64!) triggers the reverb in Fluidsynth, which has midi-cc 91. Can I change that behaviour? It is NOT caused by the keyboard, as the midi-cc for the pedal is correctly assigned to 64.
I don’t know if you can set that, and you can wait for an answer, but…
If you mean you asked Zynthian to do a software update, I would suggest that you load a fresh image to an SD card from https://os.zynthian.org/ instead. The update mechanism has problems switching between versions.
I could do that, sure. But: does every image work on a (rather old) Zynthian V3? I remember having problems using a newer image after a died SD-Card and was lucky to find the old image
You can’t update an old Gorgona. I couldn’t say the result of doing so.
You should try the latest image. We try keeping backward compatibility with the oldest zynthian hardware, including V1, V2 & V3.