Google Maps turn by turn Nav app does not always work properly. About 50% of the time, the app will "talk out loud" to me and the other it just does the turn by turn navigation without "speaking." I seem to have the problem in my car. Could it be an issue with my phone being bluetooth enabled at the same time? Help! Verizon wants to do a hard re-set or send me another phone. Would prefer not do download everything again.