Ubuntu no sound, dummy output, and no sound card detected
OK, I got it worked. Thanks for the help of Jean.
I use the solution here solution.
Open /etc/modprobe.d/alsa-base.conf and add the following line at the end:
options snd-hda-intel dmic_detect=0
Then:
pulseaudio -k && sudo alsa force-reload
You will hear the sound.