// And a master clock selector.
QAction *master_clock_action = new QAction("Use as master clock", &menu);
master_clock_action->setCheckable(true);
- if (global_mixer->get_output_card_index() != -1) {
+ if (global_mixer->get_output_card_index() != -1 && global_mixer->get_output_card_is_master()) {
master_clock_action->setChecked(false);
master_clock_action->setEnabled(false);
} else if (global_mixer->get_master_clock() == signal_num) {