Hey @907jon I am sorry for us getting to this one so late but hopefully the information I am providing will be useful to others in the future! So this kind of issue is most of the time caused by the previously loaded material is not heating up to temp fully causing a slight blockage and excess pressure in the hotend results. In turn this will cause the feed system to grind up the material. To resolve this we would normally recommend to purge the ABS out with a cold pull which you can find the instructions for here. Give these a shot if you still run into issues or feel free to reach out to us. Thanks!