I recently had a remote start installed and once the vehicle is started using the remote start my Onstar shuts down and the Nav voice does not work (Instead of hearing a voice, all I hear is a buzzing sound). Even after turning off the car and restarting just using the key, the system still does not work. I took it back to the shop and we reset the system back unplugging the battery, which worked momentarily, however it has relapsed, and is not working again. Any insight on the problem would be helpful. Thanks

 

I would take it back to the installer and explain the issue to them.