Hi.  I'm helping a group of young people (age 10+) build a project around the Octo + R.Pi 4.

We have a dead output channel (6) at the Octo card:
https://github.com/Audio-Injector/Octo/issues/45
... and not sure what to do about it.

We want to replace the everything-to-all-channels config with one that allows us to play at least 4 independent channels.

We would like to know things like impedances, input + output voltage ranges, driver rate limits, whether the outputs are balanced or ground-bonded.

We have no board layout, connection diagrams, programming manual or data sheet.

The Linux audio documentation is ... chaotic and assumes a high level of prior knowledge.

We have no way of contacting the manufacturer, as far as we can see.

Any suggestions?