I'm smoking baby back ribs and using my new Maverick ET-733 for the first time. My target temp for the MES is 235 degrees but the ET-733 shows the BBQ continually swinging from 225-246 back and forth. I never saw this before with any other therm I've used. Does the MES digital controller swing like this to keep the heat at an average of 235 or is this a controller going bad? I've got the BBQ never the front of the 2nd rack near the door but I plan to move it to the rear when I remove the ribs to wrap them in foil for the next 2 hour cook.