Hello everybody. I am a student at University of Nebraska Kearney. I am the guy who fixes the 3d printers here. I never have worked with an ultimaker until this one. It started off great but over time started having little problems that have now escalated to most the prints will not finish with out imperfections. I think it is the extruder, because the tension on the filament is pretty strong. I try to adjust the white tap that relieves pressure but it can't budge. The spring feels like it is stiff and won't compress or loosen. Is this normal for all extruders that come with the ultimaker or am I looking in the wrong place? This is a video of what i am talking about.