No Stereo sound on Recalbox 4.0

[webodan]

Thread title.

I used to have stereo sound when I installed the distro, but it misteriously disappeared. I use the 3.5mm jack and I've probed my cable and the audio output on the board with a tester: the hardware is fine and has both channels and ground. I also tried changing audio output from auto to hdmi or from hdmi to jack but no luck. On the recalbox log it shows Plback channels: Mono and I have no options in GUI to switch from mono to stereo, so I'm kinda stuck without options right now.

[Substring]

@webodan when you say the sound is mono : do you have only 1 speaker outputting sound ?

[webodan]

@Substring exactly, no matter what i do only one channel sounds. when i plug in headphones it's specially noticeable that only one side works

[Dragu]

Perhaps I have an answer. The Audio plug from the Raspberry PI 3 has 4 instead of 3 contacts. At top video, and if you plugin a normal stereo audio plug, you have mono. You need an iphone Audio jack, here the difference

[Substring]

@Dragu that's because the pi can output composite video through the jack phone. I haven't had the opportunity yet to test the jack output, but as far as i remember, never had sound problems

[paradadf]

@Dragu you can see the needed conector here:
https://github.com/recalbox/recalbox-os/wiki/Connect-your-recalbox-to-a-CRT-with-composite-(EN)