diff --git a/desktopenvs/hyprlua/scripts/presence-detect.sh b/desktopenvs/hyprlua/scripts/presence-detect.sh
index 2166685..9a2fb65 100755
--- a/desktopenvs/hyprlua/scripts/presence-detect.sh
+++ b/desktopenvs/hyprlua/scripts/presence-detect.sh
@@ -63,6 +63,17 @@ _camera_id() {
     fi
 }
 
+# True if any process OTHER than this daemon currently holds the real camera
+# open — a video call, howdy, etc. `fuser` lists same-user holders without root
+# (every camera app runs as us), and we only ever call this when we aren't
+# reading the camera ourselves, so any holder is another app. If fuser isn't
+# installed we return false: the tick then just tries the camera and the Python
+# helper's busy/in-use path (exit 3) still covers an already-held device.
+_camera_in_use() {
+    command -v fuser >/dev/null 2>&1 || return 1
+    fuser -s "/dev/video${1}" 2>/dev/null
+}
+
 # Prints current CPU-or-RAM usage as a fraction (0..1): the higher of the
 # core-count-normalized 1-minute load average and the used-RAM fraction. Load
 # average is a cheap, sampling-free proxy for "CPU busy" — no extra measurement
@@ -147,10 +158,21 @@ while true; do
     fi
 
     DEVICE="$(_camera_id)"
+    now="$(date +%s)"
+
+    # Back-off: if another app already holds the camera (a video call, howdy,
+    # ...), don't even try to read it — attempting would be pointless (we'd just
+    # get EBUSY) and a simultaneous open could make the app itself fail. A camera
+    # in use is proof you're present, so mark presence and wait it out instead.
+    if _camera_in_use "$DEVICE"; then
+        LAST_MOTION="$now"; touch "$PRESENCE_FLAG"; _start_inhibit
+        sleep "$(_next_interval)"
+        continue
+    fi
+
     # Run the OpenCV motion detector; stderr suppressed to keep the journal clean.
     python3 "$PYTHON_DETECT" "$DEVICE" 2>/dev/null
     rc=$?
-    now="$(date +%s)"
     case $rc in
         # Motion (0) or camera busy/in use (3): user is present. rc=3 means
         # another app (a video call, howdy) is holding the camera, which is