Make laptop ALSA routing match Pi rover

pi/asound.debian-laptop.conf

@@ -1,32 +1,36 @@
-# ALSA routing for the Debian laptop rover profile.
+# Dedicated ALSA routing for the Debian laptop rover profile.
 #
-# This file intentionally mirrors the logical device names used by the Pi rover
-# audio setup. roverd can keep sending horn audio to "horn", forwarded browser
-# audio to "forward", and TTS to ALSA's default playback path without caring
-# which physical sound card is underneath the profile.
+# This intentionally mirrors pi/asound.conf as closely as a normal PC can:
+# one fixed hardware card, one dmix playback engine, separate softvol controls
+# for TTS/horn/forwarded audio, and a raw capture alias for the rover mic.
+#
+# This is NOT meant to preserve normal desktop audio behavior. The laptop rover
+# installer disables PipeWire/PulseAudio so roverd owns the audio hardware like
+# the Raspberry Pi rover does. If the laptop's real speaker/mic card is not ALSA
+# card 0, change the hw:0,0/card 0 references below to the card shown by:
+#   aplay -l
+#   arecord -l
 
-pcm.roverd_playback {
-	type plug
-
-	# Use the system's first normal ALSA playback device as the physical sink.
-	# This avoids referencing "default" here, because this file replaces
-	# pcm.!default below and using it as a slave would recurse.
-	slave.pcm "sysdefault"
+# Mix multiple playback clients in software with a fixed low-cost format.
+pcm.dmixer {
+    type dmix
+    ipc_key 1024
+    ipc_perm 0666
+    slave {
+        pcm "hw:0,0"
+        format S16_LE
+        rate 16000
+        channels 1
+        period_time 0
+        period_size 1024
+        buffer_size 4096
     }
-
-pcm.roverd_capture {
-	type plug
-
-	# The media publisher records from "default"; with pcm.!default below that
-	# capture side resolves here. Keeping capture separate from playback lets the
-	# asym default expose ordinary microphone input while playback goes through
-	# the TTS softvol path.
-	slave.pcm "sysdefault"
 }
 
+# TTS volume control (used by default playback path).
 pcm.tts_softvol {
     type softvol
-	slave.pcm "roverd_playback"
+    slave.pcm "dmixer"
     control {
         name "TTSMaster"
         card 0
@@ -35,9 +39,10 @@ pcm.tts_softvol {
     max_dB 12.0
 }
 
+# Horn volume control.
 pcm.horn_softvol {
     type softvol
-	slave.pcm "roverd_playback"
+    slave.pcm "dmixer"
     control {
         name "HornMaster"
         card 0
@@ -46,9 +51,10 @@ pcm.horn_softvol {
     max_dB 12.0
 }
 
+# Forwarded audio volume control.
 pcm.forward_softvol {
     type softvol
-	slave.pcm "roverd_playback"
+    slave.pcm "dmixer"
     control {
         name "ForwardMaster"
         card 0
@@ -57,6 +63,7 @@ pcm.forward_softvol {
     max_dB 12.0
 }
 
+# Per-source playback PCMs.
 pcm.tts {
     type plug
     slave.pcm "tts_softvol"
@@ -72,14 +79,17 @@ pcm.forward {
     slave.pcm "forward_softvol"
 }
 
+# Capture alias used by laptop rover config defaults.
+pcm.rovermic {
+    type plug
+    slave.pcm "hw:0,0"
+}
+
+# Defaults: TTS direct playback + raw capture on the dedicated laptop sound card.
 pcm.!default {
     type asym
-
-	# Existing TTS engines play to their default ALSA output, so default playback
-	# is intentionally the TTS path. This preserves the current TTS execution
-	# model while still making the TTS volume control meaningful on laptops.
     playback.pcm "tts"
-	capture.pcm "roverd_capture"
+    capture.pcm "rovermic"
 }
 
 ctl.!default {