_pannable->pan_azimuth_control->Changed.connect_same_thread (*this, boost::bind (&VBAPanner::update, this));
_pannable->pan_elevation_control->Changed.connect_same_thread (*this, boost::bind (&VBAPanner::update, this));
_pannable->pan_width_control->Changed.connect_same_thread (*this, boost::bind (&VBAPanner::update, this));
_pannable->pan_azimuth_control->Changed.connect_same_thread (*this, boost::bind (&VBAPanner::update, this));
_pannable->pan_elevation_control->Changed.connect_same_thread (*this, boost::bind (&VBAPanner::update, this));
_pannable->pan_width_control->Changed.connect_same_thread (*this, boost::bind (&VBAPanner::update, this));