--- src/v4l2-relayd.c.orig	2026-03-30 09:59:14.804751921 -0700
+++ src/v4l2-relayd.c	2026-03-30 09:59:14.827617699 -0700
@@ -58,6 +58,7 @@
 static GstElement *input_pipeline = NULL;
 static GstElement *output_pipeline = NULL;
 static GstElement *splash_pipeline = NULL;
+static GTimer *input_timer = NULL;
 
 static gboolean    backend_pipeline_bus_call (GstBus      *bus,
                                               GstMessage  *msg,
@@ -278,6 +279,10 @@
 {
   gst_element_set_state (splash_pipeline_get (), GST_STATE_NULL);
   gst_element_set_state (input_pipeline_get (), GST_STATE_PLAYING);
+  if (input_timer == NULL)
+    input_timer = g_timer_new ();
+  else
+    g_timer_start (input_timer);
 }
 
 static void
@@ -285,6 +290,15 @@
 {
   if (input_pipeline != NULL)
     gst_element_set_state (input_pipeline, GST_STATE_NULL);
+  /* After a real streaming session (>3s), reset the output pipeline
+   * to clear stale v4l2loopback state that causes format negotiation
+   * failures when switching between camera apps.  Brief probes from
+   * PipeWire/WirePlumber (<1s) are skipped. */
+  if (input_timer != NULL && g_timer_elapsed (input_timer, NULL) > 3.0
+      && output_pipeline != NULL) {
+    gst_element_set_state (output_pipeline, GST_STATE_READY);
+    gst_element_set_state (output_pipeline, GST_STATE_PLAYING);
+  }
   if (input_pipeline != NULL)
     gst_element_set_state (splash_pipeline, GST_STATE_PLAYING);
 }