Ask for the headset profile at capture start; relaunch the daemon on update

The daemon now requests the Bluetooth headset profile itself (pactl
set-card-profile) the moment a take starts, instead of waiting for
WirePlumber to notice the stream and run its switch timer. The microphone
link comes up 0.15-0.18 s after the key instead of 0.21-0.27 s; WirePlumber
still restores A2DP when the stream goes away. First real audio is now at
0.82-0.86 s, which is the headset's own floor.

When the plugin is updated while the daemon runs, the daemon sees its source
change, exits with code 4 once idle, and the shell service relaunches it
without counting that as a crash.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Xoc9DJCViR7dg9eKzzAcfQ

daemon/sttd.py

@@ -175,6 +175,9 @@ TERMINAL_CLASSES = {"alacritty", "kitty", "foot", "com.mitchellh.ghostty", "org.
 
 LOG_FILE = os.path.join(RUNTIME, "daemon.log")
 # The CLI next to this daemon: key bindings call it by absolute path, so they work whatever Hyprland's PATH is.
+SOURCE = os.path.abspath(__file__)
+SOURCE_MTIME = os.stat(SOURCE).st_mtime
+EXIT_RELAUNCH = 4   # the source changed underneath us (plugin update): the shell service starts the new one
 STT_CLI = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), "bin", "stt")
 
 
@@ -516,6 +519,28 @@ class Binds:
 # recorder
 # ---------------------------------------------------------------------------
 
+def bt_card_for(device):
+    """bluez_input.88:C9:E8:A7:EC:7E (or bluez_input.88_C9_....0) -> bluez_card.88_C9_E8_A7_EC_7E, else None."""
+    if not device.startswith("bluez_input."):
+        return None
+    return "bluez_card." + device[len("bluez_input."):].split(".")[0].replace(":", "_")
+
+
+def request_headset_profile(device):
+    """Ask for the headset (HFP) profile the moment capture starts. WirePlumber would do the same
+    once it notices the stream, plus its switch timer: asking first saves ~0.15 s on the microphone
+    link. Fire and forget: no-op if the profile is already active, and WirePlumber still restores
+    A2DP when the stream goes away, whoever switched."""
+    card = bt_card_for(device)
+    if not card:
+        return
+    try:
+        subprocess.Popen(["pactl", "set-card-profile", card, "headset-head-unit"],
+                         stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+    except OSError:
+        pass
+
+
 class Recorder:
     def __init__(self, device):
         self.device = device
@@ -1066,6 +1091,7 @@ class Daemon:
         self.loop = None
         self.stopping = False
         self.stop_event = None
+        self.exit_code = 0
 
     # ---- state ----
     def state_msg(self, full=False):
@@ -1331,6 +1357,7 @@ class Daemon:
                 self.warm.stop()
                 self.warm = None
             self.rec = Recorder(self.cfg.get("device", "default"))
+            request_headset_profile(self.rec.device or "")
             try:
                 self.rec.start()
             except (OSError, ValueError, TypeError) as e:
@@ -1800,6 +1827,20 @@ class Daemon:
             if self.cfg.get("warmMic") and self.state == "idle" and (not self.warm or not self.warm.alive) and not self.cfg.get("warmHoldSecs", 0):
                 self.ensure_warm()
 
+    async def source_watch(self):
+        """Plugin updated while running: exit when idle so the shell service relaunches the new code."""
+        while not self.stopping:
+            await asyncio.sleep(5)
+            try:
+                changed = os.stat(SOURCE).st_mtime != SOURCE_MTIME
+            except OSError:
+                changed = False
+            if changed and self.state == "idle" and not (self.download_task and not self.download_task.done()):
+                log("daemon source changed; relaunching")
+                self.exit_code = EXIT_RELAUNCH
+                await self.shutdown()
+                return
+
     async def shutdown(self):
         if self.stopping:
             return
@@ -1843,6 +1884,7 @@ class Daemon:
         self.ensure_models()
         self.loop.create_task(self.hypr_events())
         self.loop.create_task(self.warm_watch())
+        self.loop.create_task(self.source_watch())
         for s in (signal.SIGTERM, signal.SIGINT):
             self.loop.add_signal_handler(s, lambda: self.loop.create_task(self.shutdown()))
         log(f"sttd {VERSION} listening on {SOCK}")
@@ -1866,7 +1908,9 @@ def main():
         sys.exit(3)
     # The socket is not removed on exit: the shell may already have started a
     # replacement daemon that listens on the same path.
-    asyncio.run(Daemon().run())
+    daemon = Daemon()
+    asyncio.run(daemon.run())
+    sys.exit(daemon.exit_code)
 
 
 if __name__ == "__main__":

diagnostics/bluetooth/STARTUP-TIME.md

@@ -5,49 +5,48 @@ Measured on a Sony WH-1000XM5 over an Intel AX210, PipeWire 1.6.8, WirePlumber
 
 | | before | after |
 |---|---|---|
-| mic link (eSCO) up | 0.7–1.0 s, sometimes never | 0.26–0.49 s |
+| mic link (eSCO) up | 0.7–1.0 s, sometimes never | 0.15–0.18 s |
-| first real audio at the daemon | 1.5–1.7 s, or never | 1.06–1.43 s |
+| first real audio at the daemon | 1.5–1.7 s, or never | 0.82–0.86 s |
-| "Listening" in the bar | 2.1 s on a timer, even with no audio | 1.19–1.43 s, only on real audio |
+| "Listening" in the bar | 2.1 s on a timer, even with no audio | 0.86–0.94 s, only on real audio |
+
+"After" is with the daemon recording straight from `bluez_input.<addr>`; via
+`camera-effects-mic` add ~0.25 s (its 250 ms poll and processing).
 
 ## What changed
 
 | Change | Where it lives | Gain |
 |---|---|---|
 | Daemon indicator: green on real audio only (RMS > 0.0005 or three consecutive non-silent chunks), no timer | `daemon/sttd.py` | the bar cannot claim to listen to a dead mic |
+| Daemon asks for the headset profile itself at capture start (`pactl set-card-profile`), before WirePlumber notices the stream | `daemon/sttd.py` | link up ~0.1 s sooner (0.21–0.27 s → 0.15–0.18 s); WirePlumber still restores A2DP |
+| Record from `bluez_input.<addr>` instead of `camera-effects-mic` | `~/.config/speech-to-text/config.json` | ~0.25 s sooner, no noise suppression on dictation |
 | WirePlumber profile-switch timeout 500 ms → 50 ms | `~/.local/share/wireplumber/scripts/device/autoswitch-bluetooth-profile.lua` | link up ~0.45 s sooner |
 | A2DP auto-connect rule narrowed to the XM5 | `~/.config/wireplumber/wireplumber.conf.d/bluetooth-a2dp-autoconnect.conf` | no 5 s pages of absent devices at login |
 | btusb driver patch `0002` | `/usr/lib/modules/<kernel>/updates/btusb.ko` | mic link no longer comes up silent when a page overlaps it |
 | PipeWire bluez5 patches `0001` + `0003` | `~/.local/lib/spa-0.2/bluez5/` via `SPA_PLUGIN_DIR` drop-ins | no stale-error dead takes; back-to-back takes work |
 
-Only the first row is part of this repo. The rest are machine-level and are
+Only the first two rows are part of this repo. The rest are machine-level and are
 described, with patches and measurements, in [HANDOFF.md](HANDOFF.md).
 
-## Why ~0.9 s is the floor
+## Why ~0.85 s is the floor
 
 ```
 key press
-0.00 s ─┬─ daemon starts pw-record on camera-effects-mic
+0.00 s ─┬─ daemon asks for the headset profile, starts pw-record
         │
-        │   Camera Effects notices the client (250 ms poll),
+0.07 s ─┼─ eSCO connect() reaches the kernel
-        │   opens its helper stream, WirePlumber waits 50 ms,
+        │   headset leaves sniff mode, radio sets up the link
-        │   then asks BlueZ for the headset profile
+0.16 s ─┼─ eSCO link up
-        │
-0.30 s ─┼─ eSCO link up (the headset must leave sniff mode,
-        │   then the radio sets up the synchronous link: ~0.1 s)
         │
         │   headset sends encoded digital silence while its own
-        │   mic path starts and mSBC syncs: ~0.5–0.6 s
+        │   mic path starts and mSBC syncs: ~0.6 s
         │   (measured at the decoder; Linux cannot shorten it)
         │
-0.85 s ─┼─ first non-zero samples leave the headset
+0.80 s ─┼─ first non-zero samples leave the headset
-        │   Camera Effects processing + 50 ms chunking
+        │   decode + 50 ms chunking
-0.90 s ─┴─ first real audio reaches the daemon
+0.85 s ─┴─ first real audio reaches the daemon
 ```
 
-What is left on the Linux side is the ~0.25 s before the profile switch is
+Nothing measurable is left on the Linux side.
-even requested. The daemon could ask for the headset profile itself when
-capture starts, but the WirePlumber autoswitch script only restores a profile
-it switched, so the daemon would have to restore A2DP too. Not done.
 
 The headset's silence after link-up and the eSCO setup are hardware. Words
 spoken in the first ~0.9 s are lost unless the microphone is already in

plugin/Service.qml

@@ -105,6 +105,11 @@ Item {
     }
     onExited: function(code, status) {
       root.state = ({})
+      if (code === 4) {   // the daemon saw its own source change (plugin update) and asked to be relaunched
+        restartTimer.interval = 500
+        restartTimer.restart()
+        return
+      }
       root.restarts += 1
       if (code !== 3 && root.restarts >= 3) root.daemonError = "daemon keeps exiting (code " + code + ") — check the log"
       restartTimer.interval = code === 3 ? 5000 : Math.min(10000, 1000 + root.restarts * 1000)  // 3 = another instance holds the lock