I’ve been trying to have my Garmin Zumo 346 gps announcements whilst talking/listening on the intercom but it just doesn’t work. My friend has his music playing on his ST1 overlayed with the intercom. Why can’t the gps be overlayed too? Can it be done? I have just found that the manual says if connected by gps pairing, its instructions will interrupt the intercom. Is there another way to connect the gps so that it will overlay the instructions? Can it be introduced on a new firmware?