diff --git a/gtk2_ardour/mixer_strip.cc b/gtk2_ardour/mixer_strip.cc
index 2b260bcb5a..78d69ba6bf 100644
--- a/gtk2_ardour/mixer_strip.cc
+++ b/gtk2_ardour/mixer_strip.cc
@@ -407,7 +407,8 @@ MixerStrip::set_route (boost::shared_ptr<Route> rt)
 			midi_input_enable_button = manage (new StatefulToggleButton);
 			midi_input_enable_button->set_name ("MixerMidiInputEnableButton");
 			midi_input_enable_button->set_image (*img);
-			midi_input_enable_button->signal_toggled().connect (sigc::mem_fun (*this, &MixerStrip::midi_input_toggled));
+			midi_input_enable_button->signal_button_press_event().connect (sigc::mem_fun (*this, &MixerStrip::input_active_button_press), false);
+			midi_input_enable_button->signal_button_release_event().connect (sigc::mem_fun (*this, &MixerStrip::input_active_button_release), false);
 			ARDOUR_UI::instance()->set_tip (midi_input_enable_button, _("Enable/Disable MIDI input"));
 		} else {
 			input_button_box.remove (*midi_input_enable_button);
@@ -1915,16 +1916,40 @@ MixerStrip::hide_things ()
 	processor_box.hide_things ();
 }
 
-void
-MixerStrip::midi_input_toggled ()
+bool
+MixerStrip::input_active_button_press (GdkEventButton* ev)
+{
+	/* nothing happens on press */
+	return true;
+}
+
+bool
+MixerStrip::input_active_button_release (GdkEventButton* ev)
 {
 	boost::shared_ptr<MidiTrack> mt = midi_track ();
 
 	if (!mt) {
-		return;
+		return true;
 	}
 
-	mt->set_input_active (midi_input_enable_button->get_active());
+	if (mt->input_active()) {
+		if (Keyboard::modifier_state_contains (ev->state, Keyboard::ModifierMask (Keyboard::PrimaryModifier|Keyboard::SecondaryModifier))) {
+			/* turn all other tracks using this input off */
+			_session->set_exclusive_input_active (mt, false);
+		} else {
+			mt->set_input_active (false);
+		}
+
+	} else {
+		if (Keyboard::modifier_state_contains (ev->state, Keyboard::ModifierMask (Keyboard::PrimaryModifier|Keyboard::SecondaryModifier))) {
+			/* turn all other tracks using this input on */
+			_session->set_exclusive_input_active (mt, true);
+		} else {
+			mt->set_input_active (true);
+		}
+	}
+
+	return true;
 }
 
 void
diff --git a/gtk2_ardour/mixer_strip.h b/gtk2_ardour/mixer_strip.h
index de907a3607..863aab2ee6 100644
--- a/gtk2_ardour/mixer_strip.h
+++ b/gtk2_ardour/mixer_strip.h
@@ -188,7 +188,8 @@ class MixerStrip : public RouteUI, public Gtk::EventBox
 	std::string longest_label;
 
 	void midi_input_status_changed ();
-	void midi_input_toggled ();
+	bool input_active_button_press (GdkEventButton*);
+	bool input_active_button_release (GdkEventButton*);
 
 	gint    mark_update_safe ();
 	guint32 mode_switch_in_progress;
diff --git a/libs/ardour/ardour/io.h b/libs/ardour/ardour/io.h
index 865971b377..062abac4f4 100644
--- a/libs/ardour/ardour/io.h
+++ b/libs/ardour/ardour/io.h
@@ -107,6 +107,7 @@ class IO : public SessionObject, public Latent
 	int disconnect (Port *our_port, std::string other_port, void *src);
 	int disconnect (void *src);
 	bool connected_to (boost::shared_ptr<const IO>) const;
+	bool connected_to (const std::string&) const;
 	bool connected () const;
 	bool physically_connected () const;
 
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 004ff41f83..6b9010642c 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -238,6 +238,7 @@ class Session : public PBD::StatefulDestructible, public PBD::ScopedConnectionLi
 	boost::shared_ptr<Route> route_by_name (std::string);
 	boost::shared_ptr<Route> route_by_id (PBD::ID);
 	boost::shared_ptr<Route> route_by_remote_id (uint32_t id);
+	void routes_using_input_from (const std::string& str, RouteList& rl);
 
 	bool route_name_unique (std::string) const;
 	bool route_name_internal (std::string) const;
@@ -608,6 +609,7 @@ class Session : public PBD::StatefulDestructible, public PBD::ScopedConnectionLi
 	void set_listen (boost::shared_ptr<RouteList>, bool, SessionEvent::RTeventCallback after = rt_cleanup, bool group_override = false);
 	void set_record_enabled (boost::shared_ptr<RouteList>, bool, SessionEvent::RTeventCallback after = rt_cleanup, bool group_override = false);
 	void set_solo_isolated (boost::shared_ptr<RouteList>, bool, SessionEvent::RTeventCallback after = rt_cleanup, bool group_override = false);
+	void set_exclusive_input_active (boost::shared_ptr<Route> rt, bool others_on);
 
 	PBD::Signal1<void,bool> SoloActive;
 	PBD::Signal0<void> SoloChanged;
diff --git a/libs/ardour/io.cc b/libs/ardour/io.cc
index 5c2cdcf53e..13d22e6592 100644
--- a/libs/ardour/io.cc
+++ b/libs/ardour/io.cc
@@ -1519,6 +1519,18 @@ IO::connected_to (boost::shared_ptr<const IO> other) const
 	return false;
 }
 
+bool
+IO::connected_to (const string& str) const
+{
+	for (PortSet::const_iterator i = _ports.begin(); i != _ports.end(); ++i) {
+		if (i->connected_to (str)) {
+			return true;
+		}
+	}
+
+	return false;
+}
+
 void
 IO::process_input (boost::shared_ptr<Processor> proc, framepos_t start_frame, framepos_t end_frame, pframes_t nframes)
 {
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index ecdd9bca8d..d4af9b6766 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -2466,6 +2466,62 @@ Session::io_name_is_legal (const std::string& name)
 	return true;
 }
 
+void
+Session::set_exclusive_input_active (boost::shared_ptr<Route> rt, bool others_on)
+{
+	RouteList rl;
+	vector<string> connections;
+
+	PortSet& ps (rt->input()->ports());
+
+	for (PortSet::iterator p = ps.begin(); p != ps.end(); ++p) {
+		p->get_connections (connections);
+	}
+
+	for (vector<string>::iterator s = connections.begin(); s != connections.end(); ++s) {
+		routes_using_input_from (*s, rl);
+	}
+
+	/* scan all relevant routes to see if others are on or off */
+
+	bool others_are_already_on = false;
+
+	for (RouteList::iterator r = rl.begin(); r != rl.end(); ++r) {
+		if ((*r) != rt) {
+			boost::shared_ptr<MidiTrack> mt = boost::dynamic_pointer_cast<MidiTrack> (*r);
+			if (mt) {
+				if (mt->input_active()) {
+					others_are_already_on = true;
+					break;
+				}
+			}
+		}
+	}
+
+	/* globally reverse other routes */
+
+	for (RouteList::iterator r = rl.begin(); r != rl.end(); ++r) {
+		if ((*r) != rt) {
+			boost::shared_ptr<MidiTrack> mt = boost::dynamic_pointer_cast<MidiTrack> (*r);
+			if (mt) {
+				mt->set_input_active (!others_are_already_on);
+			}
+		}
+	}
+}
+
+void
+Session::routes_using_input_from (const string& str, RouteList& rl)
+{
+	boost::shared_ptr<RouteList> r = routes.reader ();
+
+	for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
+		if ((*i)->input()->connected_to (str)) {
+			rl.push_back (*i);
+		}
+	}
+}
+
 boost::shared_ptr<Route>
 Session::route_by_name (string name)
 {