mac-capture: Don't read channels for disconnected audio device

Co-authored-by: PatTheMav <[email protected]>

plugins/mac-capture/mac-audio.c

@@ -1007,7 +1007,7 @@ static obs_properties_t *coreaudio_properties(bool input, void *data)
 	property = obs_properties_add_bool(props, "enable_downmix", obs_module_text("CoreAudio.Downmix"));
 	obs_property_set_modified_callback2(property, coreaudio_downmix_changed, ca);
 
-	if (ca != NULL) {
+	if (ca != NULL && ca->au_initialized) {
 		uint32_t channels = get_audio_channels(ca->speakers);
 		ensure_output_channels_visible(props, ca, channels);