You're suppose to shut the door! That might have been it. lol Don't use the 3-2-1 method and have had pretty good results. Just wasn't proud of what I produced this time.
Temps were pretty constant. Same grade of ribs I usually use as well. Never had a problem cooking 4 to a regular shelf. I put the ribs in and about 3 hours in rotated the racks and swapped locations. Don't normally open door to check too often. Definitely not fall off the bone but not burned either. Kind of at a loss, guess I'll have to smoke more and try again.