pulseaudio – No sound at all?

After installing a supplied update to Ubuntu 23.04 (up until then Ubuntu ran without any problem on my Dell Latitude E6500), all of a sudden there’s no more sound (not within Chromium, not in YouTube, not in VLC, nowhere).
A day later however 23.10 became available. But alas, upgrading 23.04 to 23.10 did not solve the sound problem.

Additional information:

1. My machine has no additional sound card (there’s just default HDA Intel).
2. I’ve checked answers to sound questions here but I got none the wiser.