I upgraded to Kubuntu 20.04.1 and audio stopped working. PulseAudio volume control (pavucontrol) shows that it is using a Dummy output device.

There are some solutions found on search engines. The frequently posted one is to add kernel module options for the intel-hda device. These solutions didn’t work for me.

My hardware is a desktop PC with an audio front panel. It doesn’t have jack sense which might part of problem here(?). This hasn’t been in issue on prior versions of Ubuntu. The onboard audio would always be the default device.

Here’s how I got PulseAudio to use the onboard audio. Use aplay to find the hardware number. Below we see that my device is card 1.

$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: HDMI [HDA ATI HDMI], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: Generic [HD-Audio Generic], device 0: ALC892 Analog [ALC892 Analog]
  Subdevices: 0/1
  Subdevice #0: subdevice #0

Configure PulseAudio to use that device in default.pa. Edit ~/.config/pulse/default.pa. The part below with device=hw:1 corresponds to card 1 above.

.nofail
.include /etc/pulse/default.pa

load-module module-alsa-sink device=hw:1

I ran pulseaudio -k to restart the PulseAudio daemon. (Or reboot for good measure). In alsamixer, I unmuted the Master, Headphone, Front volume controls. These volume settings seem to persist over reboot.

PulseAudio volume control still shows the device as (unplugged)(unavailable) but audio works anyways.

As I said, my set up doesn’t have jack sense so it always outputs to both the back panel and front panel. If this is something you need then further investigation is necessary.