diff --git a/image-recipe/configs/archipelago-kiosk-launcher.sh b/image-recipe/configs/archipelago-kiosk-launcher.sh
index 2f34a33e..1e227760 100644
--- a/image-recipe/configs/archipelago-kiosk-launcher.sh
+++ b/image-recipe/configs/archipelago-kiosk-launcher.sh
@@ -83,25 +83,33 @@ xset s noblank 2>/dev/null || true
 pkill -u archipelago -f 'chromium.*localhost' 2>/dev/null || true
 sleep 1
 
-# GPU vs headless (#36). On a real kiosk display with a GPU, GPU rasterization is
-# fast. On a GPU-less / headless server (no /dev/dri), --enable-gpu-rasterization
-# forces GPU paths that fall back to software compositing and SPIN a full core at
-# ~92% CPU, saturating the node. Detect the GPU and pick safe flags accordingly.
+# GPU vs headless (#36, choppy-audio incident 2026-06-28). --enable-gpu-rasterization
+# spins a dedicated GPU process at 55-92% CPU even on real GPU hardware (Intel HD 5500)
+# because under X11 it falls back to software compositing anyway — that CPU
+# starvation is what caused choppy HDMI audio. --in-process-gpu avoids the
+# separate process; GpuRasterization is also disabled via --disable-features below.
+# On a GPU-less / headless server (no /dev/dri), disable GPU entirely instead.
 if [ -e /dev/dri/card0 ] || [ -e /dev/dri/renderD128 ]; then
-    GPU_FLAGS="--enable-gpu-rasterization --num-raster-threads=2"
+    GPU_FLAGS="--in-process-gpu --num-raster-threads=1"
 else
     GPU_FLAGS="--disable-gpu --num-raster-threads=1"
 fi
 
+ARCHIPELAGO_UID=$(id -u archipelago)
+
 while true; do
-    sudo -u archipelago env DISPLAY=:0 HOME=/home/archipelago chromium --kiosk \
+    # XDG_RUNTIME_DIR must be passed explicitly — without it Chromium's audio
+    # backend can't find PipeWire-Pulse's socket at /run/user/<uid>/pulse/native,
+    # falls back to raw ALSA "default", fails to connect, and produces no audio
+    # at all with no visible error (--noerrdialogs suppresses it).
+    sudo -u archipelago env DISPLAY=:0 HOME=/home/archipelago XDG_RUNTIME_DIR=/run/user/$ARCHIPELAGO_UID chromium --kiosk \
       --app=http://localhost/kiosk?safe_area_x=${KIOSK_SAFE_AREA_X_PX:-0}\&safe_area_y=${KIOSK_SAFE_AREA_Y_PX:-0} \
       --noerrdialogs \
       --disable-infobars \
       --disable-translate \
       --no-first-run \
       --check-for-update-interval=31536000 \
-      --disable-features=TranslateUI,MetricsReporting,AutofillServerCommunication,PasswordManagerEnabled \
+      --disable-features=TranslateUI,MetricsReporting,AutofillServerCommunication,PasswordManagerEnabled,GpuRasterization \
       --disable-session-crashed-bubble \
       --disable-save-password-bubble \
       --disable-suggestions-service \
diff --git a/image-recipe/configs/archipelago-kiosk.service b/image-recipe/configs/archipelago-kiosk.service
index ad996448..b388c4f5 100644
--- a/image-recipe/configs/archipelago-kiosk.service
+++ b/image-recipe/configs/archipelago-kiosk.service
@@ -25,8 +25,11 @@ RestartSec=5
 # backend (it caused the .198 receive timeout + deploy storms). Cap CPU + memory
 # so a runaway kiosk can never take the whole machine down; Delegate so the cap
 # also binds the chromium/Xorg children in this unit's cgroup.
+# CPUQuota=75% (0.75 cores) was too tight even for normal playback — the kiosk
+# was throttled ~40% of the time, which is what caused choppy HDMI audio on
+# archy-x250-exp (2026-06-28 incident). 200% (2 cores) gives enough headroom.
 Delegate=yes
-CPUQuota=75%
+CPUQuota=200%
 # Raised from 1500M/1200M: a Framework (Tiger Lake) kiosk sat at 806M used /
 # 1.1G peak, riding the old MemoryHigh reclaim-throttle line — the throttling
 # itself was the perceived UI lag. Keep Max well above real peaks; High stays
diff --git a/image-recipe/configs/asound.conf b/image-recipe/configs/asound.conf
new file mode 100644
index 00000000..8a1f1f07
--- /dev/null
+++ b/image-recipe/configs/asound.conf
@@ -0,0 +1,7 @@
+pcm.!default {
+    type pulse
+    hint.description "Default ALSA Device (via PulseAudio)"
+}
+ctl.!default {
+    type pulse
+}
diff --git a/scripts/deploy-tailscale.sh b/scripts/deploy-tailscale.sh
index 51853135..28a2b506 100755
--- a/scripts/deploy-tailscale.sh
+++ b/scripts/deploy-tailscale.sh
@@ -425,6 +425,22 @@ deploy_node() {
         ' 2>/dev/null || true
     fi
 
+    # ── Deploy ALSA default-device config ────────────────────────────
+    ASOUND_CONF="$PROJECT_DIR/image-recipe/configs/asound.conf"
+    if [ -f "$ASOUND_CONF" ]; then
+        step "Deploying ALSA default-device config"
+        scp $SSH_OPTS "$ASOUND_CONF" "$TARGET:/tmp/asound.conf" 2>/dev/null || true
+        ssh $SSH_OPTS "$TARGET" '
+            if ! diff -q /tmp/asound.conf /etc/asound.conf >/dev/null 2>&1; then
+                sudo cp /tmp/asound.conf /etc/asound.conf
+                echo "   Installed"
+            else
+                echo "   Unchanged"
+            fi
+            rm -f /tmp/asound.conf
+        ' 2>/dev/null || true
+    fi
+
     # ── Step 18: NTP + swap ──────────────────────────────────────────
     step "Ensuring NTP + swap"
     ssh $SSH_OPTS "$TARGET" '
diff --git a/scripts/deploy-to-target.sh b/scripts/deploy-to-target.sh
index c93f3a50..69824a6d 100755
--- a/scripts/deploy-to-target.sh
+++ b/scripts/deploy-to-target.sh
@@ -463,6 +463,22 @@ deploy_secondary() {
         ' 2>/dev/null || true
     fi
 
+    # Deploy ALSA default-device config (routes ALSA "default" through PulseAudio/PipeWire)
+    ASOUND_CONF="$PROJECT_DIR/image-recipe/configs/asound.conf"
+    if [ -f "$ASOUND_CONF" ]; then
+        echo "   Syncing ALSA default-device config to .$SEC_LABEL..."
+        scp $SSH_OPTS "$ASOUND_CONF" "$SEC_TARGET:/tmp/asound.conf" 2>/dev/null || true
+        ssh $SSH_OPTS "$SEC_TARGET" '
+            if ! diff -q /tmp/asound.conf /etc/asound.conf >/dev/null 2>&1; then
+              sudo cp /tmp/asound.conf /etc/asound.conf
+              echo "   ALSA default-device config installed"
+            else
+              echo "   ALSA default-device config unchanged"
+            fi
+            rm -f /tmp/asound.conf
+        ' 2>/dev/null || true
+    fi
+
     # Dev mode + FileBrowser
     ssh $SSH_OPTS "$SEC_TARGET" '
         # Dev mode
@@ -805,6 +821,23 @@ if [ "$LIVE" = true ]; then
       ' 2>/dev/null || true
     fi
 
+    # Deploy ALSA default-device config (routes ALSA "default" through
+    # PulseAudio/PipeWire — without it Chromium's raw ALSA fallback can't
+    # reach the HDMI sink and kiosk HDMI audio is silent).
+    ASOUND_CONF="$PROJECT_DIR/image-recipe/configs/asound.conf"
+    if [ -f "$ASOUND_CONF" ]; then
+      scp $SSH_OPTS "$ASOUND_CONF" "$TARGET_HOST:/tmp/asound.conf" 2>/dev/null || true
+      ssh $SSH_OPTS "$TARGET_HOST" '
+        if ! diff -q /tmp/asound.conf /etc/asound.conf >/dev/null 2>&1; then
+          sudo cp /tmp/asound.conf /etc/asound.conf
+          echo "   ALSA default-device config installed"
+        else
+          echo "   ALSA default-device config unchanged"
+        fi
+        rm -f /tmp/asound.conf
+      ' 2>/dev/null || true
+    fi
+
     # Deploy Claude API proxy (auto-install if missing)
     progress "Setting up Claude API proxy"
     ssh $SSH_OPTS "$TARGET_HOST" '