I have a bunch of NUC10s I am using for a project (both i3 and i5s) onto which I have installed Ubuntu 20.04 LTS. These NUC models have no audio jack and rely on HDMI for sound. But I have no sound. I performed the same install on NUC7s and had sound over HDMI without incident.
After googling for 2 days, I think I've tried every suggested fix from this site and many others. The only success I've had is to upgrade the kernel from 5.13. I've tried 5.14,5.15, and 5.16. Sound works fine on all three. However, once I upgrade the kernel I cannot shutdown or reboot. It hangs at [OK] Reached target Reboot (or Shutdown). I tried using an older kernel - 5.4 - and applying numerous edit recommendations to /etc/modprobe.d/alsa-base.conf -- still no sound.
Just as a test, I installed SuSE 15.3 which worked fine (which for various reasons I cannot use for this project). I also tried Debian 11, on which the sound fails as well. So honestly I'm out of ideas. If push comes to shove, I'll choose sound over shutdown, but I really don't want to.
I'm open to ideas on both the sound and booting fronts if anybody has any solid fixes for either. My current test box is a BXNUC103FNKN2.
Additional Requested Information:
$ pactl list sinks
Sink #0
State: RUNNING
Name: auto_null
Description: Dummy Output
Driver: module-null-sink.c
Sample Specification: s16le 2ch 44100Hz
Channel Map: front-left,front-right
Owner Module: 14
Mute: no
Volume: front-left: 65536 / 100% / 0.00 dB, front-right: 65536 / 100% / 0.00 dB
balance 0.00
Base Volume: 65536 / 100% / 0.00 dB
Monitor Source: auto_null.monitor
Latency: 80 usec, configured 500 usec
Flags: DECIBEL_VOLUME LATENCY SET_FORMATS
Properties:
device.description = "Dummy Output"
device.class = "abstract"
device.icon_name = "audio-card"
Formats:
pcm