I did Master Reset twice in last week. Problem not solved. After driving few minutes, GPS slows down. Its behind 40-100 feet by actual location of the car. On Hi-Ways , this distance could go up 1/2 mile or more. I was reading that in late 2014 you could recalibrate using TSB 14-0037. This TSB is not available anymore. Is any other solution to this problem. I have another problem. Car makes hissing sound ( you can hear on the driver side) on the road when you press the gas paddle. Mechanic says there is no code , so its ok. Just wondering what it could be? It kind of annoying when driving.