[LibreElec 19.2.1] Audio 3.5mm Jack output is not working on ROCKPro64

    I installed LibreElec 19.2.1 on a ROCKPro64 (see link below for full hardware specs). However the audio jack 3.5mm output is not working. There is no sound.

    All output sound setting have been tested.

    The sound is not mute.

    Code
    # cat .kodi/userdata/guisettings.xml
[...]
<audio>
<mute>false</mute>
<fvolumelevel>1.000000</fvolumelevel>
</audio>
</settings>

    I order to reproduce, just play a sound on a ROCKPro64 with speakers plugged to the audio output and audio output setting set on analogue.

    For hardware specs, see links below:

    Device's webpage

    Device's wiki

    I have already asked on the forum

    Audio 3.5mm Jack output is not working on ROCKPro64