Hey John — sorry for my late reply. I hope the following will help, but I should start with asking whether the Terrain has the IntelliLink system.
Outside of that, I think you’re experiencing the following when attempting to make a call: you’re using what’s called “Bluetooth passthrough” — which bypasses the car’s microphones and allows you direct access to the phone’s mic.
As far as streaming apps via Bluetooth Audio, do you have the vehicle in Bluetooth audio mode? I’ve had no problems doing this in all kinds of 2011 and 2012 GM vehicles with iOS and Android devices.
