It is the custom audio option of the CHrome add-on settings. These options get loaded when /storage/.kodi/addons/browser.chrome/bin/chrome-start is started. But when I use Chrome-launcher these options seem to be overriden. If I am correct, the value that I put in the custom audio field is directly loaded in the $ALSA_DEVICE variable.
I think the problem lies in the Chrome-launcher addon, it does not recognize the location of Google-Chrome. So I have to manualy tell it where it is, but /storage/.kodi/addons/browser.chrome/bin/chrome-start is not recognised as chrome. So I select the actual Chrome location, thus al the tweaks in chrome-start are not carried over.
Maybe I should to try to stop and start pulseaudio like it is in /storage/.kodi/addons/browser.chrome/bin/chrome-start.
I have it running now on my laptop (live usb) which does have an analog output, I made no custom config or script changes. I'm going to run this live-usb on my NUC tonight to see if it works. If not, it probably has to do with the custom audio.
I have tested the live-usb, no audio when used on my NUC. So I started to check the chrome-launcher files to see if I could find a starting point to begin fixing this. As I found out if you use a custom path to Chrome, which is needed with your Chrome addon, the script.sh is completely skipped. Thus the chrome-start of your add-on is called on opening of a url. But in this case all the chrome_OPTS variables are not loaded. Which is a problem if you need to use a custom audio device to get sound. To get around this I hardcoded the options, which is not a long term solution becasue this might be overwritten with a future update. For now, I have shortcuts in Kodi Favorites and working audio .
# start chrome
# $chrome_OPTS \
LD_PRELOAD=/usr/lib/libGL.so $ADDON_DIR/chrome-bin/chrome \
--alsa-output-device=plughw:0,3 --enable-gpu-rasterization --enable-accelerated-2d-canvas --ignore-gpu-blacklist --enable-accelerated-video \
--test-type [email protected] \
2>&1 | tee $ADDON_LOG_FILE