iPhone 5 and GPS Directions via Bluetooth
 

When I use my iPhone 5 to talk on the phone in my 2013 Hardtop it works flawlessly. Automatically connects, calls come in and go out perfectly through the car speakers. So clearly my Bluetooth pairing was and continues to be, a success. However, when I use Google Maps, directions only sometimes come through the car speakers. It is intermittent. When I use the same phone, same Google Maps app with another car it operates flawlessly through that cars speakers via Bluetooth. So there is something wrong with this app and my car. Has anyone else experienced this and knows a fix?