Reading current state from the audio interface

[sinefabula]

Hi! I've read your code and the control messages you sniffed from USB but haven't found anything except for a brief mention — did you manage to reverse engineer how the current values are read from the audio interface? Or the official app just stores them somewhere and updates as needed? I'm working on a fork which would run without GUI (need that on my headless Raspberry Pi), and right now it just reads the matrix from a .txt file and 'uploads' the settings to the audio interface but I might add proper TUI in the future. So I was thinking it would be great if the settings were always in sync between the device and the app.

[soerenbnoergaard]

Hi,

I am glad to hear you found the project useful.

I did not go any further reverse engineering the readback of the device's current state. As I also mention, I had issues using the program while Jack was running so in the end, it was not too useful to me.

Instead, I ended up modifying the kernel driver to support the EVO interface so the mixer-controls could be controlled through native tools like alsa-mixer. It is not polished (you need to bypass some error-checks when loading the module) but works well once loaded. Using this method, the parameters can also be read back so you do not have to mirror them locally. Perhaps this is useful to you as well?

https://github.com/soerenbnoergaard/snd-usb-audio-audient-evo8

Best regards,
Søren