Comment 4 for bug 1876499

I found the following:

https://ubuntuforums.org/showthread.php?t=2421187

Based on that I edited

/etc/modprobe.d/alsa-base.conf

and added this to the end of the file:

# Manual entry to allow audio via headphones because NVIDIA drivers break the built-in audio
options snd-hda-intel model=clevo-p950
options snd-hda-intel probe_mask=0x1

with the probe_mask entry the headphones would work again.
with the model entry the speakers also got to work.

For people with other hardware and the same problem you can retrieve the codec of the system with

$ cat /proc/asound/card0/codec*

And check what model entry you need to use matching your codec in the following site:

https://www.infradead.org/~mchehab/rst_conversion/sound/hd-audio/models.html

This is in any case a workaround and it would be best if the update hadn't broken it.