I’ve built a Raspberry Pi 2 with Ubuntu Core and installed
chromium-mir-kiosk. This kiosk works fine and displays web pages exactly as it should. However, I don’t get audio when the page plays an mp3. In
pulsemixer I only see one output, “built in analogue audio”; HDMI isn’t mentioned. How might I go about debugging this? I don’t know where the problem may lie; in chrome, in pulseaudio, in mir, in Ubuntu Core. There are lots of questions about this on the web but they all suggest adding an HDMI setting in
/boot/config.txt, which doesn’t exist in Ubuntu Core.
snap logs chromium-mir-kiosk does show
2019-10-06T19:28:05Z chromium-mir-kiosk.chromium-mir-kiosk: ALSA lib pcm.c:2266:(snd_pcm_open_noupdate) Unknown PCM plug:default 2019-10-06T19:28:05Z chromium-mir-kiosk.chromium-mir-kiosk: [3682:3703:1006/192805.506637:ERROR:alsa_util.cc(204)] PcmOpen: plug:default,No such file or directory
which might be relevant and might not.