if (_session) {
_session->TransportStateChange.connect_same_thread (_session_connections, boost::bind (&MidiClockTicker::transport_state_changed, this));
_session->TransportLooped.connect_same_thread (_session_connections, boost::bind (&MidiClockTicker::transport_looped, this));
if (_session) {
_session->TransportStateChange.connect_same_thread (_session_connections, boost::bind (&MidiClockTicker::transport_state_changed, this));
_session->TransportLooped.connect_same_thread (_session_connections, boost::bind (&MidiClockTicker::transport_looped, this));