diff --git a/.gitignore b/.gitignore
index 9e70f57ac5..af96cafb86 100644
--- a/.gitignore
+++ b/.gitignore
@@ -19,7 +19,6 @@ a.out
 bin/
 !openpilot/starpilot/galaxy/bin/
 !openpilot/starpilot/soloist/pulseaudio/bin/
-!openpilot/starpilot/soloist/bluealsa/bin/
 
 # created at launch for comma hardware PYTHONPATH (PC uses editable installs via pyproject.toml)
 /msgq
@@ -48,7 +47,6 @@ bin/
 !openpilot/tools/replay/libmedia_mux.so
 !openpilot/starpilot/soloist/pulseaudio/lib/*.so
 !openpilot/starpilot/soloist/pulseaudio/modules/*.so
-!openpilot/starpilot/soloist/bluealsa/lib/*.so
 *.a
 st[0-9A-Za-z][0-9A-Za-z][0-9A-Za-z][0-9A-Za-z][0-9A-Za-z][0-9A-Za-z]
 *.unchunked
diff --git a/.trail/learnings/2026-10-22-rebasing-stardust-onto-the-existing-pr-danny.md b/.trail/learnings/2026-10-22-rebasing-stardust-onto-the-existing-pr-danny.md
new file mode 100644
index 0000000000..485eb3ef35
--- /dev/null
+++ b/.trail/learnings/2026-10-22-rebasing-stardust-onto-the-existing-pr-danny.md
@@ -0,0 +1,23 @@
+---
+title: Rebasing Stardust onto the existing PR-Smaller-4 split
+author: Danny
+date: 2026-10-22
+branch: integration/stardust-smaller4-20261022
+touches:
+  - openpilot/starpilot/galaxy/spotify_setup.py
+  - openpilot/starpilot/galaxy/tests/test_spotify.mjs
+  - openpilot/starpilot/galaxy/tests/test_spotify_setup.py
+  - openpilot/starpilot/galaxy/web/css/galaxy.css
+  - openpilot/starpilot/galaxy/web/js/spotify.js
+  - openpilot/starpilot/soloist/backend.py
+  - openpilot/starpilot/soloist/bluealsa/README.md
+  - openpilot/starpilot/soloist/preferences.py
+  - openpilot/starpilot/soloist/tests/test_bluealsa_upgrade.py
+---
+
+## Decided
+Use backup/Stardust-Spotify-Companion-pre-split-20261019 as the replay boundary when rebasing the October 22 Stardust tip onto PR-Smaller-4. The split already contains the older features, and PR-Smaller-5 is an ancestor of PR-Smaller-4. Replay the 13 later commits, preserving upstream UI and troubleshooting links.
+## Tried and ruled out
+A plain rebase tries 121 old commits, causing duplicate feature conflicts and temporarily reintroducing logging removed later. The partial clone lacks object 4569f738be4f7dab405c63f8db8f23872c1be190 for the intermediate volume commit; the net diff from ddc9244f0b to the saved Stardust tip is available and preserves the final volume behavior.
+## Watch out
+Do not overwrite active PR-Smaller-4 worktree edits. Keep backup branches and a binary patch. Refresh the combined prebuilt inventory receipt. Soloist tests need local socket permission; Galaxy server tests additionally require the native Params library. No device build or deployment was performed.
diff --git a/openpilot/starpilot/galaxy/spotify_setup.py b/openpilot/starpilot/galaxy/spotify_setup.py
index 4e6455cc63..aee132a8cd 100644
--- a/openpilot/starpilot/galaxy/spotify_setup.py
+++ b/openpilot/starpilot/galaxy/spotify_setup.py
@@ -166,8 +166,10 @@ class SpotifySetup:
       raise SetupRejected('Invalid Spotify settings')
     values = {**current.__dict__, **{fields[key]: value for key, value in payload.items()}}
     changes_output = values['output'] != current.output or values['output_address'] != current.output_address
+    # Flipping between Spotify and the already chosen phone is a playback control; picking a different phone is setup.
+    if values['phone_address'] != current.phone_address:
+      self._require_parked('change the phone')
     if values['source'] != current.source or values['phone_address'] != current.phone_address:
-      self._require_parked('change the music source')
       if values['phone_address']:
         match = next((d for d in self.status(session)['devices'] if d['address'] == str(values['phone_address']).upper()), None)
         if match is None:
diff --git a/openpilot/starpilot/galaxy/tests/test_spotify.mjs b/openpilot/starpilot/galaxy/tests/test_spotify.mjs
index dd57127b33..50e7f8bbbd 100644
--- a/openpilot/starpilot/galaxy/tests/test_spotify.mjs
+++ b/openpilot/starpilot/galaxy/tests/test_spotify.mjs
@@ -5,7 +5,7 @@ import { SpotifyFeed, SpotifyPage, archivePreflight, importProblem, installCheck
 const setup = {
   enabled: true, parked: true, keyPresent: true, audioReady: true,
   release: { installed: true, version: "1.3.9.32", expires: "2027-01-14T00:00:00+00:00", daysLeft: 80, level: "ok", expired: false },
-  preferences: { deviceName: "StarPilot", cacheMb: 256, initialVolume: 60, output: "bluetooth", outputAddress: "AA:BB:CC:DD:EE:FF", outputName: "Car" },
+  preferences: { deviceName: "StarPilot", cacheMb: 256, initialVolume: 100, output: "bluetooth", outputAddress: "AA:BB:CC:DD:EE:FF", outputName: "Car" },
   devices: [{ address: "AA:BB:CC:DD:EE:FF", name: "Car", connected: true }], service: null,
   import: { state: "idle" }, maxUploadBytes: 64 * 1024 * 1024, archiveName: "soloist_release_arm64.tar.gz", cacheChoices: [100, 256],
   links: { download: DOWNLOAD_PAGE, key: "https://developer.spotify.com/dashboard/soloist", help: "https://developer.spotify.com/" },
diff --git a/openpilot/starpilot/galaxy/tests/test_spotify_setup.py b/openpilot/starpilot/galaxy/tests/test_spotify_setup.py
index 48ab354ea8..50ce0cb3e9 100644
--- a/openpilot/starpilot/galaxy/tests/test_spotify_setup.py
+++ b/openpilot/starpilot/galaxy/tests/test_spotify_setup.py
@@ -181,7 +181,9 @@ def test_phone_source_requires_park_and_a_paired_device_without_spotify(owner):
   setup, state, layout, _ = owner
   state['parked'] = False
   with pytest.raises(SetupRejected, match='Park'):
-    setup.save_preferences(SESSION, {'source': 'phone'})
+    setup.save_preferences(SESSION, {'source': 'phone', 'phoneAddress': 'AA:BB:CC:DD:EE:FF'})
+  assert setup.save_preferences(SESSION, {'source': 'phone'})['preferences']['source'] == 'phone'  # flipping source works while driving
+  assert setup.save_preferences(SESSION, {'source': 'spotify'})['preferences']['source'] == 'spotify'
   state['parked'] = True
   with pytest.raises(SetupRejected, match='Pair your phone'):
     setup.save_preferences(SESSION, {'source': 'phone', 'phoneAddress': '11:22:33:44:55:66'})
diff --git a/openpilot/starpilot/galaxy/web/css/galaxy.css b/openpilot/starpilot/galaxy/web/css/galaxy.css
index 7e41e826e7..308fa63157 100644
--- a/openpilot/starpilot/galaxy/web/css/galaxy.css
+++ b/openpilot/starpilot/galaxy/web/css/galaxy.css
@@ -1757,13 +1757,12 @@ progress { max-width: 100%; accent-color: var(--primary); }
 input[type="range"].gx-slider.gx-slider--galaxy,
 [data-theme="light"] input[type="range"].gx-slider.gx-slider--galaxy { height: 10px; border: none;
   background: linear-gradient(90deg, var(--secondary), var(--primary)) 0 0 / var(--fill, 0%) 100% no-repeat, var(--surface-container-high); }
-.gx-spotify-now__main { display: flex; gap: var(--sp-3); align-items: center; min-width: 0; }
+.gx-spotify-now__main { display: flex; gap: var(--sp-3); align-items: center; justify-content: center; min-width: 0; }
 .gx-spotify-now__text { min-width: 0; }
 .gx-spotify-now__text h3, .gx-spotify-now__text p { margin: 0; }
 .gx-spotify-now__progress { display: grid; gap: 2px; }
-.gx-spotify-now__controls { align-items: center; flex-wrap: wrap; }
+.gx-spotify-now__controls { align-items: center; justify-content: center; flex-wrap: wrap; }
 .gx-spotify-now__play { min-width: 64px; font-size: 1.4rem; }
-.gx-spotify-now__volume { display: flex; flex: 1 1 160px; align-items: center; gap: var(--sp-2); min-width: 0; }
 /* Auto Learn results use existing cards and plot colors. */
 .gx-flm__facts { display: flex; flex-wrap: wrap; gap: 1rem 2rem; }
 .gx-flm__facts dd { margin: .3rem 0 0; }
diff --git a/openpilot/starpilot/galaxy/web/js/spotify.js b/openpilot/starpilot/galaxy/web/js/spotify.js
index cce6dddfe0..785a00c968 100644
--- a/openpilot/starpilot/galaxy/web/js/spotify.js
+++ b/openpilot/starpilot/galaxy/web/js/spotify.js
@@ -258,7 +258,7 @@ export const SpotifyPage = {
     setup: null, busy: false, error: "", uploadProgress: null, now: Date.now(),
     installOpen: false, removeOpen: false, resetOpen: false, showSetup: false, downloadStarted: false,
     archiveFile: null, archiveMagicError: "", archiveChecking: false, archiveSelection: 0, installAttempted: false, installBaseline: null,
-    keyValue: "", keyEditing: false, nameValue: "", volumeDraft: null, pauseDraft: null, skipDraft: null,
+    keyValue: "", keyEditing: false, nameValue: "", pauseDraft: null, skipDraft: null,
   }),
   mounted() {
     this.feed = new SpotifyFeed({ publish: (value) => Object.assign(this, value, { now: Date.now() }), unauthorized: this.unauthorized })
@@ -388,11 +388,6 @@ export const SpotifyPage = {
       this.skipDraft = null
       if (Number.isFinite(value)) return this.feed.post("./api/spotify/preferences", { skipMute: value })
     },
-    commitVolume(event) {
-      const volume = Math.round(Number(event.target.value))
-      this.volumeDraft = null
-      if (Number.isInteger(volume) && volume >= 0 && volume <= 100) return this.control("volume", { volume })
-    },
     openInstall() { this.chooseAgain(); Object.assign(this, { installOpen: true, downloadStarted: false }) },
     closeInstall() { this.installOpen = false },
     markDownloadStarted() {
@@ -444,7 +439,7 @@ export const SpotifyPage = {
       <section v-if="setup" class="gx-card gx-aa-step" aria-labelledby="gx-music-source-title">
         <h3 id="gx-music-source-title">Music Source</h3>
         <label class="gx-stack"><span>Play music from</span>
-          <select class="gx-field" :value="setup.preferences.source || 'spotify'" :disabled="busy || !setup.parked" @change="chooseSource">
+          <select class="gx-field" :value="setup.preferences.source || 'spotify'" :disabled="busy" @change="chooseSource">
             <option value="spotify">Spotify Connect on the comma</option>
             <option value="phone">Phone over Bluetooth</option>
           </select>
@@ -480,7 +475,7 @@ export const SpotifyPage = {
             <option value="test">Silent test (no speaker)</option>
           </select></label>
         </template>
-        <small v-if="!setup.parked" class="gx-note">Put the car in Park or use offroad mode to change the source.</small>
+        <small v-if="phoneSource && !setup.parked" class="gx-note">Put the car in Park or use offroad mode to change the phone.</small>
       </section>
 
       <section v-if="setup && setupDone && !phoneSource" class="gx-card gx-aa-step gx-aa-home gx-spotify-now" aria-labelledby="gx-spotify-now-title">
@@ -501,10 +496,8 @@ export const SpotifyPage = {
           <button type="button" class="gx-btn gx-spotify-now__play" :aria-label="playing ? 'Pause' : 'Play'" :disabled="!can.has(playing ? 'pause' : 'play') && !!track" @click="togglePlay">
             <i :class="playing ? 'bi bi-pause-fill' : 'bi bi-play-fill'" aria-hidden="true"></i></button>
           <button type="button" class="gx-icon-btn" aria-label="Next" :disabled="!can.has('skip_next')" @click="control('next')"><i class="bi bi-skip-end-fill"></i></button>
-          <label v-if="player.volume !== null" class="gx-spotify-now__volume"><i class="bi bi-volume-up" aria-hidden="true"></i>
-            <input type="range" class="gx-slider gx-slider--galaxy" min="0" max="100" step="1" :value="volumeDraft ?? player.volume" :style="{ '--fill': (volumeDraft ?? player.volume) + '%' }" aria-label="Volume"
-              @input="volumeDraft = Number($event.target.value)" @change="commitVolume" /></label>
         </div>
+        <small v-if="setup.enabled && player?.loggedIn && player.volume !== null" class="gx-note">Volume {{ player.volume }}% - change in Spotify app if needed, otherwise use car volume</small>
         <div v-if="setup.enabled && player?.loggedIn && !player.active" class="gx-stack">
           <button type="button" class="gx-btn gx-btn--tonal" @click="control('activate')">
             <i class="bi bi-broadcast" aria-hidden="true"></i> Move Spotify to {{ setup.preferences.deviceName || 'StarPilot' }}</button>
diff --git a/openpilot/starpilot/soloist/backend.py b/openpilot/starpilot/soloist/backend.py
index 0cf6009a86..e7de95f23e 100644
--- a/openpilot/starpilot/soloist/backend.py
+++ b/openpilot/starpilot/soloist/backend.py
@@ -34,6 +34,7 @@ SYSTEM_ALSA_CONFIG = Path('/usr/share/alsa/alsa.conf')
 # The Android Auto media channel format every head unit must offer; the pipe runs on the system clock,
 # so it produces exactly real-time audio (silence when paused) whether or not anyone reads it.
 PIPE_RATE, PIPE_CHANNELS, PIPE_BYTES_PER_FRAME = 48000, 2, 4
+PLAYER_VOLUME = 100  # level is the car's/speaker's job; the saved initial_volume preference is ignored
 
 
 class BackendUnavailable(RuntimeError):
@@ -55,7 +56,7 @@ def alsa_config(address: str, base: Path = SYSTEM_ALSA_CONFIG) -> str:
   if any(character in str(base) for character in '\n\r<>"'):
     raise BackendUnavailable('Invalid system ALSA configuration path')
   return (f'<{base}>\n' + bluealsa_runtime.alsa_plugins() +
-          f'\npcm.{PCM_NAME} {{\n  type bluealsa\n  device "{address}"\n  profile "a2dp"\n  softvol "true"\n' +
+          f'\npcm.{PCM_NAME} {{\n  type bluealsa\n  device "{address}"\n  profile "a2dp"\n  volume "100+"\n  softvol "true"\n' +
           '  hint { show on description "StarPilot Spotify output" }\n}\n')
 
 
@@ -117,7 +118,7 @@ def player_launch(layout: Layout, prefs: Preferences, api_key: str) -> Launch:
   # The key must be an argument: Soloist documents no file, fd or environment alternative.
   argv = [str(layout.current / 'soloist'), '--device-name', prefs.device_name, '--api-key', api_key,
           '--data-dir', str(layout.state), '--cache-dir', str(layout.cache), '--cache-size', str(prefs.cache_mb),
-          '--initial-volume', str(prefs.initial_volume), '--ws', '127.0.0.1:0']
+          '--initial-volume', str(PLAYER_VOLUME), '--ws', '127.0.0.1:0']
   env = {'HOME': str(paths['home']), 'XDG_RUNTIME_DIR': str(paths['run']), 'PATH': '/usr/bin:/bin',
          'PULSE_SERVER': f'unix:{paths["socket"]}'}
   return Launch(argv, env)
diff --git a/openpilot/starpilot/soloist/bluealsa/README.md b/openpilot/starpilot/soloist/bluealsa/README.md
index da355e9261..5be68d5cb1 100644
--- a/openpilot/starpilot/soloist/bluealsa/README.md
+++ b/openpilot/starpilot/soloist/bluealsa/README.md
@@ -24,7 +24,9 @@ inactivity and short input interruptions. It inserts silence; it does not
 reconstruct missing music or eliminate interference. Playback leaves `hwcompat`
 at its default so a disconnected output is not silently consumed. Both paths
 explicitly set `softvol "true"` to preserve the previous software-volume mode
-instead of adopting 5.0's new native-volume default. Initial device volume state
+instead of adopting 5.0's new native-volume default. Playback also opens
+at `volume "100+"` (100%, unmuted) because 5.0 persists each device's last volume
+and applies it to samples in soft-volume mode. Phone capture is left unchanged. Initial device volume state
 is separate from 4.1; the user's existing 4.1 state is never rewritten.
 
 The build retains SBC reception, SBC/LDAC transmission, and oFono support. The
diff --git a/openpilot/starpilot/soloist/preferences.py b/openpilot/starpilot/soloist/preferences.py
index c2fb971290..e2e0c6f83b 100644
--- a/openpilot/starpilot/soloist/preferences.py
+++ b/openpilot/starpilot/soloist/preferences.py
@@ -19,7 +19,7 @@ MUTE_MAX = 1.5
 class Preferences:
   device_name: str = 'StarPilot'
   cache_mb: int = 256
-  initial_volume: int = 60
+  initial_volume: int = 100
   output: str = 'bluetooth'           # or 'android_auto' (the car's media channel), or 'test' (a silent sink)
   output_address: str = ''
   output_name: str = ''
diff --git a/openpilot/starpilot/soloist/tests/test_bluealsa_upgrade.py b/openpilot/starpilot/soloist/tests/test_bluealsa_upgrade.py
index 326eeee78b..36b9408ccc 100644
--- a/openpilot/starpilot/soloist/tests/test_bluealsa_upgrade.py
+++ b/openpilot/starpilot/soloist/tests/test_bluealsa_upgrade.py
@@ -19,6 +19,8 @@ def test_capture_and_playback_select_matching_private_plugins():
   for config in (capture, playback):
     assert runtime.alsa_plugins() in config
     assert 'softvol "true"' in config
+  assert 'volume "100+"' in playback  # saved state must never leave Spotify quiet or muted
+  assert 'volume' not in capture  # phone audio level was already right; leave it to the phone
   assert 'hwcompat "silence"' in capture
   assert 'hwcompat' not in playback
 
diff --git a/prebuilt.json b/prebuilt.json
index 19b11e2da4..a51a5b8d6e 100644
--- a/prebuilt.json
+++ b/prebuilt.json
@@ -1 +1 @@
-{"protected_inventory_sha256": "d2437878b07e69107e1dbfd6ca4f498524a730e7346c1e8082468685453a1260", "schema_version": 1}
+{"protected_inventory_sha256": "db604052cc7583a2c2a82def4aa1cfa0c50149a69bf2f051ecceb9062e94e90d", "schema_version": 1}