At Sherman Hill, I use camera 3 a lot and during a long time. I now experience that I cannot switch back to camera 1, instead it switches to camera 8. It happened to me during the Midnight Magnet scenario, short before Hermosa, same during a timetable drive fro Cheyenne, also some miles before Hermosa. Until now I did not experience the issue at other routes. I drive using keyboard and mouse, but I have an XBOX controller coupled to my computer.
I also experienced the same thing. What did i do is i save the scenario, exit to main menu and then load the saved game. It's solve that problem.