diff --git a/gtk2_ardour/port_group.cc b/gtk2_ardour/port_group.cc
index c47bda3030..70fd5a1b84 100644
--- a/gtk2_ardour/port_group.cc
+++ b/gtk2_ardour/port_group.cc
@@ -178,7 +178,20 @@ PortGroupList::refresh ()
 
 			if (p.substr(0, strlen ("system:")) == "system:" || p.substr (0, strlen ("alsa_pcm:")) == "alsa_pcm:") {
 				/* system: or alsa_pcm: prefix */
-				_system.add_port (p);
+
+				/* see if this port is already in one of the system: bundles */
+				std::vector<boost::shared_ptr<ARDOUR::Bundle> >::iterator i = _system.bundles.begin();
+				while (i != _system.bundles.end()) {
+					if ((*i)->uses_port (p)) {
+						break;
+					}
+					++i;
+				}
+
+				if (i == _system.bundles.end()) {
+					/* it's not already in there, so add it */
+					_system.add_port (p);
+				}
 			} else {
 				if (p.substr(0, client_matching_string.length()) != client_matching_string) {
 					/* other (non-ardour) prefix */
diff --git a/gtk2_ardour/port_matrix_grid.cc b/gtk2_ardour/port_matrix_grid.cc
index 13e1dcf4c2..f63cd231d7 100644
--- a/gtk2_ardour/port_matrix_grid.cc
+++ b/gtk2_ardour/port_matrix_grid.cc
@@ -200,15 +200,15 @@ PortMatrixGrid::button_press (double x, double y, int b)
 		PortMatrix::State const s = _port_matrix->get_state (
 			our_bundle, our_channel, other_bundle, other_channel
 			);
-				
+
 		if (s == PortMatrix::ASSOCIATED || s == PortMatrix::NOT_ASSOCIATED) {
 
 			bool const n = !(s == PortMatrix::ASSOCIATED);
 			
-		_port_matrix->set_state (
-			our_bundle, our_channel, other_bundle, other_channel,
+			_port_matrix->set_state (
+				our_bundle, our_channel, other_bundle, other_channel,
 				n, 0
-			);
+				);
 		}
 
 		require_render ();