- width_button.unset_flags (Gtk::CAN_FOCUS);
- hide_button.unset_flags (Gtk::CAN_FOCUS);
- input_button.unset_flags (Gtk::CAN_FOCUS);
- output_button.unset_flags (Gtk::CAN_FOCUS);
- solo_button->unset_flags (Gtk::CAN_FOCUS);
- mute_button->unset_flags (Gtk::CAN_FOCUS);