Kubuntu 26.04 — Getting the headphones working

A PC typically has three ways of producing sound:

• the speakers in the PC (if any),
• the speakers in the display, connected through HDMI,
• the headphones, connected through a cable.

By default, in Kubuntu 26.04, the headphones don't work. My system is one with AMD Ryzen (in case that matters).

This is annoying, because after generations of sound systems in Linux (Open Sound System, ALSA, PulseAudio, and now PipeWire), a user's expectation is that it works out-of-the-box.

The solution is:
After each reboot:

1. Plug in headphones.

2.

KDE System Settings Input & Output > Sound > Playback Devices: Select "Ryzen HD Audio Controller Analog Stereo". Select Port: "Headphones (unplugged)". Select Profile: "Pro Audio". 

Credit: This solution comes from https://discuss.kde.org/t/wired-earphones-do-not-work-out-of-the-box/46408