No experience with the Cardo, but the Sena 30k and 50s sound the same with each connection. 30k is BT4 and 50s is BT5 so no issues with the older setup. This is on a Samsung S9+ and S21+. There is a media button in the pulldown menu that allows you to pick the audio source when multiple BT devices are connected so it's easy to switch back and forth to test. You can even select both simultaneously if you want, but for voice commands to work correctly the connection to the phone has to be present.