diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index a198f0eac6..c7b66c1139 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -502,6 +502,8 @@ public:
 	samplecnt_t worst_route_latency () const  { return _worst_route_latency; }
 	samplecnt_t worst_latency_preroll () const;
 
+	PBD::Signal0<void> LatencyUpdated;
+
 	struct SaveAs {
 		std::string new_parent_folder;  /* parent folder where new session folder will be created */
 		std::string new_name;           /* name of newly saved session */
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 6db282c1eb..4214681753 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -6475,6 +6475,7 @@ Session::update_latency (bool playback)
 	}
 
 	DEBUG_TRACE (DEBUG::Latency, "JACK latency callback: DONE\n");
+	LatencyUpdated (); /* EMIT SIGNAL */
 }
 
 void