After fiddling a little with PulseAudio and Alsa to make Ardour work, my built-in speakers, built-in mic, and plugged in headphones and headphones mic have all disappeared from sound settings.
After reinstalling Alsa and PulseAudio (a la, this Reddit post), I can hear sounds on speakers (or on headphones when they're plugged in) and can control volume, but I can't select headphones microphone, and can't see any devices in sound settings.
How do I get my built-in speakers and headphones to appear in sound settings again?
I'm using elementary OS 5.1.7 Hera, on a Dell XPS 13 (9380). alsamixer told me that my sound card uses Realtek ALC3271 codec.