No audio in/out of audio jack

#1

board:
rock 3A 4GB (RS117-131220615368)

problem:
have tried at least 5 different images, including official supported xcfe Debian, but cannot get any audio from the 3.5 mm jack, using plug with tip and 3 rings. Also checked with an oscilloscope that no audio is present, so it is not a connector issue.
From a software perspective all seems OK. Using from command line paplay and pactl , or aplay, or from firefox some film with audio, all seems normal. No error messages.
The pulse audio mixer shows audio coming from the source. But on the jack: nothing.
This board is from a series with a production error in a power supply chip, that I came across while scanning this forum. Perhaps this has any relation to the rk809 codec part not functioning on its hardware I/O side?
Any suggestions welcome.

#2

From a software perspective all seems OK.
…
But on the jack: nothing.

In fact, there is such an image.
The default setting of the software (or driver) may be “OFF” for the output control of the final stage of the device.
Depending on the image, the corresponding part default setting is “ON”.
—
If the image is the former, it is exactly the symptoms you described. (ex: Armbian @ kernel 5.xx, radxa’s “latest” [by green letter])
On the other hand, the latter will output the sound correctly without changing the settings. (ex: Armbian @ kernel 6.xx, Manjaro KDE @ kernel 6.xx)
—
You seem to have concerns about the rk809, but from the schematics and “radxa”'s explanation,I think it’s unlikely.
First, you need to present the specific name of the image you used.