diff --git a/libs/ardour/ardour/route.h b/libs/ardour/ardour/route.h
index 9fd1630d1e..09441c038e 100644
--- a/libs/ardour/ardour/route.h
+++ b/libs/ardour/ardour/route.h
@@ -355,7 +355,7 @@ public:
 	virtual void apply_latency_compensation ();
 
 	samplecnt_t  set_private_port_latencies (bool playback) const;
-	void         set_public_port_latencies (samplecnt_t, bool playback) const;
+	void         set_public_port_latencies (samplecnt_t, bool playback, bool with_latcomp) const;
 
 	samplecnt_t signal_latency() const { return _signal_latency; }
 	samplecnt_t playback_latency (bool incl_downstream = false) const;
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 50610cf90e..1244a9ffdf 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -1432,6 +1432,7 @@ private:
 	void remove_monitor_section ();
 
 	void update_latency (bool playback);
+	void set_owned_port_public_latency (bool playback);
 	bool update_route_latency (bool reverse, bool apply_to_delayline, bool* delayline_update_needed);
 	void initialize_latencies ();
 	void set_worst_output_latency ();
diff --git a/libs/ardour/port.cc b/libs/ardour/port.cc
index ee872ad125..25510a92ae 100644
--- a/libs/ardour/port.cc
+++ b/libs/ardour/port.cc
@@ -367,7 +367,7 @@ Port::set_public_latency_range (LatencyRange const& range, bool playback) const
 
 	if (_port_handle) {
 		LatencyRange r (range);
-		if (externally_connected () && 0 == (_flags & TransportSyncPort)) {
+		if (externally_connected () && 0 == (_flags & TransportSyncPort) && sends_output () == playback) {
 #if 0
 			r.min *= _speed_ratio;
 			r.max *= _speed_ratio;
@@ -399,10 +399,6 @@ Port::set_private_latency_range (LatencyRange& range, bool playback)
 			             _private_capture_latency.min,
 			             _private_capture_latency.max));
 	}
-
-	/* push to public (port system) location so that everyone else can see it */
-
-	set_public_latency_range (range, playback);
 }
 
 const LatencyRange&
@@ -426,14 +422,14 @@ Port::private_latency_range (bool playback) const
 }
 
 LatencyRange
-Port::public_latency_range (bool /*playback*/) const
+Port::public_latency_range (bool playback) const
 {
 	/*Note: this method is no longer used. It exists purely for debugging reasons */
 	LatencyRange r;
 
 	if (_port_handle) {
-		r = port_engine.get_latency_range (_port_handle, sends_output() ? true : false);
-		if (externally_connected () && 0 == (_flags & TransportSyncPort)) {
+		r = port_engine.get_latency_range (_port_handle, playback);
+		if (externally_connected () && 0 == (_flags & TransportSyncPort) && sends_output () == playback) {
 #if 0
 			r.min /= _speed_ratio;
 			r.max /= _speed_ratio;
@@ -450,7 +446,7 @@ Port::public_latency_range (bool /*playback*/) const
 		DEBUG_TRACE (DEBUG::LatencyIO, string_compose (
 				     "GET PORT %1: %4 PUBLIC latency range %2 .. %3\n",
 				     name(), r.min, r.max,
-				     sends_output() ? "PLAYBACK" : "CAPTURE"));
+				     playback ? "PLAYBACK" : "CAPTURE"));
 	}
 
 	return r;
@@ -487,7 +483,7 @@ Port::get_connected_latency_range (LatencyRange& range, bool playback) const
 
 				if (remote_port) {
 					lr = port_engine.get_latency_range (remote_port, playback);
-					if (externally_connected () && 0 == (_flags & TransportSyncPort)) {
+					if (externally_connected () && 0 == (_flags & TransportSyncPort) && sends_output () == playback) {
 #if 0
 						lr.min /= _speed_ratio;
 						lr.max /= _speed_ratio;
diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc
index 150019df94..092c8b72eb 100644
--- a/libs/ardour/route.cc
+++ b/libs/ardour/route.cc
@@ -4412,7 +4412,12 @@ Route::apply_latency_compensation ()
 	cout << "ROUTE " << name() << " delay for " << latcomp << " (c: " << latcomp_capt << ")" << endl;
 #endif
 
-	_delayline->set_delay (latcomp > 0 ? latcomp : 0);
+	if (_delayline->set_delay (latcomp > 0 ? latcomp : 0)) {
+		DEBUG_TRACE (DEBUG::LatencyRoute, string_compose ("%1: delay changed to %2\n", _name, latcomp));
+		/* public port latency update is needed,
+		 * Session::update_latency() calls this->set_public_port_latencies()
+		 */
+	}
 }
 
 void
@@ -4975,7 +4980,7 @@ Route::set_private_port_latencies (bool playback) const
 }
 
 void
-Route::set_public_port_latencies (samplecnt_t value, bool playback) const
+Route::set_public_port_latencies (samplecnt_t value, bool playback, bool with_latcomp) const
 {
 	/* publish private latencies */
 	Glib::Threads::RWLock::ReaderLock lm (_processor_lock);
@@ -4985,9 +4990,10 @@ Route::set_public_port_latencies (samplecnt_t value, bool playback) const
 			continue;
 		}
 		if (iop->input ()) {
+			assert (iop->input () != _input); // no delivery for Input
 			iop->input ()->set_public_port_latencies (iop->input()->latency(), true);
 		}
-		if (iop->output ()) {
+		if (iop->output () && iop->output () != _output) {
 			iop->output ()->set_public_port_latencies (iop->output()->latency(), false);
 		}
 	}
@@ -4995,8 +5001,20 @@ Route::set_public_port_latencies (samplecnt_t value, bool playback) const
 	/* this is called to set the JACK-visible port latencies, which take
 	 * latency compensation into account.
 	 */
-	_input->set_public_port_latencies (value, playback);
-	_output->set_public_port_latencies (value, playback);
+	if (playback) {
+		_output->set_public_port_latencies (_output->latency (), playback);
+		if (_delayline && with_latcomp) {
+			value += _delayline->delay ();
+		}
+		_input->set_public_port_latencies (value, playback);
+	} else {
+		_input->set_public_port_latencies (_input->latency(), playback);
+		if (_delayline && with_latcomp) {
+			value += _delayline->delay ();
+		}
+		_output->set_public_port_latencies (value, playback);
+	}
+
 }
 
 /** Put the invisible processors in the right place in _processors.
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index bc20361e2f..3486d01198 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -6675,6 +6675,21 @@ restart:
 	return changed;
 }
 
+void
+Session::set_owned_port_public_latency (bool playback)
+{
+	/* special routes or IO or ports owned by the session */
+	if (auditioner) {
+		samplecnt_t latency = auditioner->set_private_port_latencies (playback);
+		auditioner->set_public_port_latencies (latency, playback, true);
+	}
+	_click_io->set_public_port_latencies (_click_io->connected_latency (playback), playback);
+
+	if (_midi_ports) {
+		_midi_ports->set_public_latency (playback);
+	}
+}
+
 void
 Session::update_latency (bool playback)
 {
@@ -6744,10 +6759,18 @@ Session::update_latency (bool playback)
 		reverse (r->begin(), r->end());
 	}
 	for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
+		/* private port latency includes plugin and I/O delay,
+		 * but no latency compensation delaylines.
+		 */
 		samplecnt_t latency = (*i)->set_private_port_latencies (playback);
-		(*i)->set_public_port_latencies (latency, playback);
+		/* However we also need to reset the latency of connected external
+		 * ports, since those includes latency compensation delaylines.
+		 */
+		(*i)->set_public_port_latencies (latency, playback, false);
 	}
 
+	set_owned_port_public_latency (playback);
+
 	if (playback) {
 		/* Processing needs to be blocked while re-configuring delaylines.
 		 *
@@ -6773,6 +6796,18 @@ Session::update_latency (bool playback)
 		update_route_latency (false, false, NULL);
 	}
 
+	for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
+		/* Publish port latency. This includes latency-compensation
+		 * delaylines in the direction of signal flow.
+		 */
+		samplecnt_t latency = (*i)->set_private_port_latencies (playback);
+		(*i)->set_public_port_latencies (latency, playback, true);
+	}
+
+	/* now handle non-route ports that we are responsible for */
+	set_owned_port_public_latency (playback);
+
+
 	DEBUG_TRACE (DEBUG::LatencyCompensation, "Engine latency callback: DONE\n");
 	LatencyUpdated (playback); /* EMIT SIGNAL */
 }