Something is draining my wife's 2015 outback's battery. Car Just purchased from prominent retail dealer. Subaru dealership has changed the rear hatch switch as a fix to the problem and tested all fuses one at a time with no problems found. The "drain" continues. We have not had to use jumper cables yet but starting the car is very sluggish. My wife has lost confidence in the vehicle ans is afraid to drive it. Please advise!