Ubuntu – No sound on HDMI Ubuntu 20.04

20.04alsahdmipulseaudiosound

I just installed Ubuntu 20.04 on my laptop which is a bit outdated:

  • CPU: Intel Core i5 CPU M 480 @ 2.67GHz
  • RAM: 4GB
  • Video card: GeForce GT 420M
  • Audio: GF108 High Definition Audio Controller NVIDIA
    and Audio 5 Series/3400 Series Chipset High Definition Audio
    HD 500GB

Overall the system is working fine, but I'm having a big issue with HDMI Audio. The display on HDMI works just perfectly, but the audio is not working at all.

I tried lots of solutions here on Ask Ubuntu, but the problem remains. Some of the solutions I tried are located in the following links:

HDMI sound not working after upgrading to 20.04

Ubuntu 18.04: Audio doesn't work unless I switch between outputs

does not detect my sound card HDMI

Also I've downloaded Ubuntu 20.04 iso again and reinstalled the system, but it doesn't work.

HDMI worked perfectly when I used Windows 10 before replacing it with Ubuntu.

When I run aplay -l I have these results:

Playback hardware Devices

When I run lspci I have these results:

Devices

In the Settings -> Sound -> Output -> Output Device I have just two options to choose from:

  • Speakers-Built-in-Audio
  • Digital Output(S/PDIF)-Built-in-Audio

On Pulseaudio > Configuration it shows:
GF108 High Definition Audio Controller
and
Built-in Audio

And in both of them all the options with HDMI are displayed with (unplugged)(unavailable).

Finally, the sound just works in my laptop, if I connect HDMI cable it display correctly but the sound keeps on my laptop.

Best Answer

After upgrading from Ubuntu 18.04 to 20.04, I noticed that pulseaudio would no longer detect HDMI audio output (plugged to an nVidia graphics card) when turning my TV on after I logged in. HDMI output is just not listed anymore in sound settings. This used to work in 18.04.

I found a workaround was to open a console and type the following command, after turning the TV on:

pulseaudio -k
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