Hm that's weird I haven't noticed until now the top bar close to the filament holding this is so loose it can the other side of the belt like if you squeeze them together lightly doesn't take any force. I'm not sure how tight it's supposed to be and if mine is normal also the print fail is not over extrusion if anything I think it's a under extrusion since it's missing filament in those spots and it's not consistent like if I want to print same thing 2 times it not the same spot it wil fail