To quote Jackson Browne: "Someone's gonna have to explain it to me."
I can understand that a wireless camera might not talk well with the unit in the cab. What I don't understand is why backing up or moving down the road would make any difference. The distance between the two is the same and 65 mph is insignificant compared to the speed of light (radio waves).
1988 Coleman Sequoia - popup (1987-2007)
2012 Roo19 - hybid (2012-2015)
2016 Mini Lite 2503S - tt (2015 - ???)
2011 Traverse LT, 3.6L, FWD
2009 Silverado Ext Cab, 5.3L, 4x4, 3.73
2016 Silverado 2500HD Dbl Cab, 6.0L 4x4, 4.10