Galaxy → Spotify and Phone Audio supports two mutually exclusive music sources: Spotify Connect (Soloist) and a paired phone's Bluetooth A2DP audio. Both use the private PulseAudio output, either Android Auto's PCM media channel or an existing BlueALSA Bluetooth output. Phone mode needs neither Soloist nor a Spotify API key. The feature's existing enable flag starts spotifyd for either source; with the phone source it never launches Soloist, and switching to it stops a running Soloist.

Phone setup

While parked, enable Bluetooth and pair the phone from Galaxy's Bluetooth page.
Choose Phone over Bluetooth, then select the paired phone.
Choose Android Auto as the output and connect projection to the head unit, or choose a different paired Bluetooth speaker/head unit.
Turn on Phone Audio. Select the comma as the phone's media audio output, then play music. Use the phone and car for playback and volume.

Changing the source stops the previous player. Pairing, source/device selection, and output changes retain Galaxy's existing session and parked/offroad checks. Phone calls, microphone forwarding, head-unit metadata and steering-wheel track controls are not implemented. AVRCP pause is attempted when Android Auto loses media focus permanently; even if the phone cannot be paused, forwarding relinquishes focus. The comma's warning speaker and global ALSA default are not changed.

Companion apps

Pairing a phone in the Android or iPhone companion app also sets it up for phone audio. The app asks the comma to open a short pairing window (Galaxy's Let a phone pair button does the same). Only one phone can claim it, only phones (Bluetooth device class) are accepted, and a confirmation code must be approved. Afterward the phone appears as the music source if none was chosen yet. Android bonds from the app; on iPhone the app asks you to tap the comma in Settings → Bluetooth. The window refuses to open while Android Auto, another pairing, or a search holds the adapter, and adapter visibility returns to what it was before. The companion's own key pairing never creates a Bluetooth bond.

Installing Soloist is only allowed from the local network, the Galaxy hotspot or the tunnel. Over the companion's Bluetooth link the page says so and sends nothing. Phone audio itself needs no install and works over Bluetooth. The Android app and the iPhone app each carry their own copy of the Galaxy pages, so they show this page only after they are updated.

Runtime behavior

The checkout bundles BlueALSA 5.0.0's daemon and matching PCM/CTL plugins for phone reception and Bluetooth output. phone_profile.py uses temporary /run overrides; the system's BlueALSA 4.1.1 installation stays intact. Phone capture uses hwcompat "silence" for continuity across input interruptions. Private ALSA configs select the matching plugins and explicitly preserve software volume. See the bundle documentation for build inputs, tests, and the old-commit rollback contract (restart music/openpilot or reboot after checkout).

Only the selected paired phone is captured. The existing trusted pairing policy still determines which phones may establish Bluetooth connections; this feature does not alter trust or erase bonds. arecord opens an ALSA plug PCM for that phone, converting to signed 16-bit 48 kHz stereo. A separate Python worker writes to the private server using AGNOS's libpulse-simple.so.0, with bounded buffers. The supervisor retries disconnects without repeatedly restarting Bluetooth. The versioned BlueALSA bundle and private PulseAudio server are included with the checkout.

Validation

Automated tests cover source migration/validation, authenticated settings, parked selection, no-Soloist startup, radio-off, disconnect/retry, temporary-profile restoration, selected-phone AVRCP targeting, and clearing audio on source changes. Run the Soloist, Galaxy Spotify setup, and Android Auto media-audio Python tests, plus node openpilot/starpilot/galaxy/tests/test_spotify.mjs.

Device acceptance remains necessary: test Android/iPhone pairing and audio, 44.1/48 kHz tracks, radio focus loss/resume, phone disconnect/reconnect, Bluetooth off/on, source switching, service restart and reboot. Test wireless Android Auto and Bluetooth output separately for radio coexistence, latency and dropouts.

Now playing on the car screen

Android Auto layouts include a Now playing card (Galaxy → Android Auto layout) that shows the title, artist and progress of Spotify or of the phone's Bluetooth player, with a background opacity setting. The supervisor publishes the snapshot in its status file; the car screen reads it once a second only while the card is enabled, and the card stays hidden when nothing is playing or an alert is up. Phone metadata comes from the phone's Bluetooth media player (BlueZ MediaPlayer1), so it depends on the phone sharing it.

Spotify Connect recovery

Pair once from Spotify's device picker on a shared Wi-Fi network or hotspot that allows device-to-device traffic. Both devices need internet access; the Galaxy hotspot and wireless Android Auto alone do not provide it. After pairing, use the same Spotify account and turn off Local device visibility in Spotify to control the comma across networks. On iPhone, allow Spotify Local Network access.

Soloist retains its account across restarts, network handoffs, output changes and cache clearing. Startup waits for an IPv4 or IPv6 default route. A disconnected Bluetooth speaker uses a private silent sink; two consecutive background checks, twenty seconds apart, trigger an output switch without restarting Soloist. A failed switch restarts playback with the saved account. Recovery never requests playback transfer from another Spotify device.

The local API checks authentication every fifteen seconds and reconnects after forty-five seconds without a response. Two minutes without a working API or a previously observed login restarts Soloist; loss of login while playing allows ten minutes for cached music. First-time pairing has no timeout. Repeated starts that never answer the API can roll back the Soloist package. A route or API response does not prove internet access; Spotify off/on retries without clearing the account.

Device acceptance remains necessary: Android/iPhone pairing on Wi-Fi and hotspots, Wi-Fi/cellular handoffs, saved-account recovery, speaker reconnects, and control across networks. See Spotify Connect and the Soloist API.