I like to use the navigation system in my SL. The problem is, I have trouble hearing it above wind noise with the top down. Actually I have trouble hearing it all the time. Neither I or my mechanic can find any way to adjust the volume. We found the ability to over-ride (or not) the radio, but not adjust the volume. Any suggestions?

 

as the nav is speaking to you...use the radio volume to turn up her voice. there also might be some settings in the nav menu for radio fade out( how much the radio will fade while the nav voice is speaking)