Index: corelib/channel.c
===================================================================
--- corelib/channel.c	(revision 1088)
+++ corelib/channel.c	(working copy)
@@ -630,7 +630,11 @@
 int opbx_queue_hangup(struct opbx_channel *chan)
 {
 	struct opbx_frame f = { OPBX_FRAME_CONTROL, OPBX_CONTROL_HANGUP };
-	chan->_softhangup |= OPBX_SOFTHANGUP_DEV;
+	/* Yeah, let's not change a lock-critical value without locking */
+	if (!opbx_mutex_trylock(&chan->lock)) {
+		chan->_softhangup |= OPBX_SOFTHANGUP_DEV;
+		opbx_mutex_unlock(&chan->lock);
+	}
 	return opbx_queue_frame(chan, &f);
 }