I just bought a 2019 SLR yesterday. About 2 hours after driving it off the lot, the Navigation button (second from the left) stopped working. I can see that the GPS is actually functioning because the split screen view shows the map and my location correctly. It's just that that second button now does nothing when I press it. I've updated the software and the map data. No help. I even pulled the radio fuse for a few minutes hoping it might reset. No joy. Suggestions?