This isn't great since it can fail when PipeWire is handling audio but no
devices are available at initialization, causing the Pulseaudio or ALSA backend
to be selected instead. Future versions of PipeWire are expected to have a
better way to detect if it's handling audio, but for now this is better than
nothing.
A config option is available for users to have the PipeWire backend be usable
even with no devices at initialization, just in case.
305201252e