Navigation/Bluetooth trouble shooting issue

I use my navigation a lot to get me where I am going. I also talk on the phone a lot via bluetooth.
The speaking directions keep playing while I am on the call and my caller can hear my nav dinging and talking. I have not yet been able to figure out a way to fix this. It is hard for me to believe that there is not a way to.
Most cars (including my previous gen Prius) did not do this.
Any tips?