phoenixperry

Hello! I have a problem with my Ultimaker 2 printer. when I start printing. I've done everything I can think of including: releveling the bed 3 times, checking the tension bands are not on the gears weirdly (they aren't perfectly centered but they are not grinding), reseating the motor, adjusting the filament tension every which way to Sunday (I even tried it with the tension screw removed) and printing at different settings. This is the default robot, which normally prints fine. Has anyone seen this? I'd really love any suggestions. thanks, Phoenix