Ubuntu – No sound on 18.04

I have a Dell xps13 that previously had 14.04 and the sound worked fine. I recently installed 18.04 and now I have no sound through either my speakers or headphones. The sound settings look like this:

(Note that there is no 'Test Sound' button. )

[Edit] I've already tried many of the fixes I've found on AskUbuntu, including:

• pulseaudio -k && sudo alsa force-reload (nothing changes)
• I've tried reinstalling alsa and pulseaudio. [/Edit]

I'm now following the Ubuntu troubleshooting guide for sound.

At step 3, entering wget -O alsa-info.sh http://www.alsa-project.org/alsa-info.sh && chmod +x ./alsa-info.sh && ./alsa-info.sh yields the output: https://pastebin.com/raw/44UDnp63

Running the code in step 4 yields https://pastebin.com/raw/YinifjQC

I've checked with pavucontrol to make sure that nothing is muted. This is what the panel looks like:

(The lower bar indicates that sound is playing, but I don't hear anything out of the speakers/headphones.)

Please help!

Edit:

As per Muntaha's suggestion, I tried

mv ~/.config/pulse ~/.config/old_pulse

and restarted. Now I have only dummy output listed:

The standard answer online to fix the 'dummy output' problem is to run pulseaudio -k && sudo alsa force-reload but this does nothing. Trying to figure out what to do now…

Further edit:

As per the solution to this question "Dummy Output" No sound in Ubuntu 16.04:

In the end, I rebooted into the bios and disabled the built-in audio, applied those changes, rebooted to Ubuntu, then rebooted again into the bios to re-enable the audio. Once back into Ubuntu after that, everything seemed to work great!

This also worked for me!