Two days ago the wireplumber package was made to replace pipewire-media-session as the latter session manager for PipeWire is considered dead upstream and will see no more releases. Unfortunately, this step was premature.
Our pipewire audio packages (pipewire-alsa, pipewire-jack and pipewire-pulse) ship configuration that prompt media-session to activate PipeWire's audio features. When these packages are not installed and the configuration is missing, PipeWire can be used for screen recording without interfering with ALSA or PulseAudio.
WirePlumber disregards this mechanism and always configures PipeWire to grab audio devices, meaning users of PulseAudio or bare ALSA experience broken audio.
The replacement has been reverted while we attempt to look for a better solution switching to WirePlumber. If you are currently not using PipeWire for audio and wireplumber got installed on your system, please reinstall pipewire-media-session and reboot to restore audio functionality.
pacman -Syu pipewire-media-session