diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc
index 9bb7126a15..c39a8ea4c2 100644
--- a/libs/ardour/route.cc
+++ b/libs/ardour/route.cc
@@ -4378,7 +4378,7 @@ Route::update_signal_latency (bool apply_to_delayline, bool* delayline_update_ne
 	 * Since the output is not used, Send::_thru_delay is not relevant, and
 	 * Send->effective_latency () should return zero.
 	 */
-	if (is_master() || output_effectively_connected ()) {
+	if (is_master() || is_monitor () || output_effectively_connected ()) {
 		_output_latency = _output->latency ();
 	} else if (_session.master_out ()) {
 		/* We cannot use `_session.master_out()->input()->latency()` because that would return capture latency.
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 8a63e451ae..d19d11b13a 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -6922,7 +6922,6 @@ Session::update_latency (bool playback)
 
 		/* prevent any concurrent latency updates */
 		Glib::Threads::Mutex::Lock lx (_update_latency_lock);
-		set_worst_output_latency ();
 		update_route_latency (true, /*apply_to_delayline*/ true, NULL);
 
 		/* release before emitting signals */
@@ -6932,7 +6931,6 @@ Session::update_latency (bool playback)
 		/* process lock is not needed to update worst-case latency */
 		lm.release ();
 		Glib::Threads::Mutex::Lock lx (_update_latency_lock);
-		set_worst_input_latency ();
 		update_route_latency (false, false, NULL);
 	}
 
@@ -6947,6 +6945,14 @@ Session::update_latency (bool playback)
 	/* now handle non-route ports that we are responsible for */
 	set_owned_port_public_latency (playback);
 
+	if (playback) {
+		Glib::Threads::Mutex::Lock lx (_update_latency_lock);
+		set_worst_output_latency ();
+	} else {
+		Glib::Threads::Mutex::Lock lx (_update_latency_lock);
+		set_worst_input_latency ();
+	}
+
 
 	DEBUG_TRACE (DEBUG::LatencyCompensation, "Engine latency callback: DONE\n");
 	LatencyUpdated (playback); /* EMIT SIGNAL */