Alpine's pipewire-pulse package ships the daemon binary but doesn't
auto-load the PA bridge module on alpine. We need to start pipewire-pulse
as a separate process with -a tcp:4713 so PA clients (librespot, mopidy)
can connect via TCP.
Layout:
- pipewire: audio server (native protocol)
- pipewire-pulse: PA-compat bridge, listens on tcp:4713 + unix:/tmp/pulse-socket
- wireplumber: session manager (loads BT modules, hot-plug handling)
- bluetoothd at /usr/lib/bluetooth/bluetoothd (not in PATH on alpine)
- Add session dbus via dbus-daemon --session (pipewire needs it)
- Clean up stale dbus.pid files on startup (host volume persists)
- audio-bridge: alpine + pipewire + pipewire-pulse + wireplumber + bluez + dbus + tini
Routes audio from librespot/mopidy/phone-BT to USB DAC (Q5K) via ALSA.
Privileged + host network for bluetoothd HCI access.
- mopidy: built from python:3.12-slim-bookworm + pip (no ghcr.io dep).
Qobuz (auth from developer.qobuz.com) + local files. PA bridge to audio-bridge.
- librespot: built from rust:1.85.1 on RPi (cross-compile too slow under qemu).
Spotify Connect target named 'Klubhaus'. PA bridge to audio-bridge.
Both mopidy and librespot build locally to avoid ghcr.io auth/rate-limit issues.
PEQ stays on Q5K side (Qudelix app, 20 bands) for source-independent EQ.
david