AC - Gas Fridge

Have a new 2014 Winnebago Sigheseer. Recently I've noticed that when I have the fridge mode set to Auto(AU), propane turned on, and then disconnect from AC, the fridge doesn't switch over to propane as it should. The only thing we've done to the unit since getting it was to install a surge protector. Don't think that would have anything to do with it. Suggestions?

Thanks