PSA for anyone who is currently experiencing an issue where mpv doesn’t play audio and sees the following error:
[ao] Failed to initialize audio driver 'pipewire'
Could not open/initialize audio device -> no sound.
The latest pipewire update breaks mpv’s pipewire driver. Upstream mpv has a patch for this, and a fixed package is already in [extra-testing]. To fix the issue, you can manually download and install an updated mpv package from here: https://archlinux.org/packages/extra-testing/x86_64/mpv/download/