I have a Garmin Varia 510 and a Garmin edge 130 bike computer.  When I am on my bike I do not hear an audible tone when cars are approaching only the visual display on the edge 130.  I have tried numerous settings to no avail.  I really need the audible alert tone.  Does the edge 130 accommodate a tone alert and if so what do I need to do set it up.  Thank you.