[Ultimaker 2 Extended - Feeder keeps skipping]

Feeder keeps skipping

Model: Ultimater 2 Extended

Hey guys,

I'm a little bit confused. After hours of printing suddenly the feeder of my Ultimaker 2 Extended started skipping: Video: https://drive.google.com/file/d/0B7KyR2ULRkeQa3U3VW1INGg1bms/view?usp=sharing

What I already tried:

 

• --> doesn't skip, when the hose is not inserted
  
• changed nozzles
  
• changed the hardness of the feeder
  

 

Have you got any ideas to help me? Because actually this skipping causes the feeder to not transport the filament fluently, so that the prints come out bad.

Thank you

Werner Koch