Ubuntu 20.04 - No sound
Solution 1:
I had the same problem. After installing Ubuntu 20.04 alongside my windows, I realized it has no sound. Reinstalling alsa-base and pulseaudio resolved it...
sudo apt-get install --reinstall alsa-base pulseaudio
sudo alsa force-reload
Source
Solution 2:
I've had luck with pavucontrol. For some reason, the output selector from the Settings->Sound dialog box didn't work for me, but with pavucontrol, I was able to select the correct output.
$ sudo apt install pavucontrol
$ pavucontrol &
Port: Headphones (unplugged) works however system recognizes it as unplugged.