Just a heads up. Grabbed a Navtv zen unit from a forum member here. It was an older unit but was never installed. I installed it in my truck and everything worked except backup chimes and the normal chimes were very loud. Did some research and it said the new firmware would fix it. The zen directions also state to go to the update website and update the firmware. I followed the directions and did the update. As soon as the unit was restarted nothing worked. I contacted navtv and they said the new update disables a chip on the older models causing them to brick. Tech support Bob then proceeded to tell me it wasn’t under warranty and I would need to pay 350 plus shipping both ways to fix it. Regardless of how old the unit was their firmware bricked the thing. So much for backing your product. The thing is really only 3 years old. What horrible customer service. Dropping this here so people with older units know not to upgrade firmware.