Thanks. I had that thought as well, so I (or so I thought) disabled retraction. Must not have worked, glad to know for sure that it's bad retraction settings.

At a certain point in every layer, the extruder reverses the filament out 2.5 cm, then continues to print even though no material is being extruded. Also makes unpleasant noises. Used Slicer experimental version to generate g-code. Looking through the G-code there are some weird moments, namely, dur...