I have a new (6 weeks) Ravelli RV100 Classic. No problems until today when the box that controls which temp sensor (back of stove vs. console) showed up with a check mark (I did not hit the 2 button to do this) and would not uncheck and default to the rear sensor despite hitting the 1 button. Tried several times. This was not a problem previously and would respond appropriately to check or uncheck command. Any thoughts on how to make the soft switch default back to the rear sensor? Can I unplug to reset? Other software tricks? Or do I need a service call?