Recently I started to get some mysterious defects in print quality. Would like to get your insights and try them out to improve.
This print, I stopped in mid-print as the problems were too prominent.
1. Randomly-appearing

2. The outer skin has these slight wiggly waves everywhere. It used to print just fine a while ago.
3. Swiss-cheese-like infill. I checked the extruder when the infill was printing to see if it stops and continues, but the white hand-turning-gear was slowly but continuously running so it's very hard to figure out what is causing it. The fact that outer/inner perimeter does not share this issue makes it difficult to assess.
It's really puzzling as some of these short-skip-within-the-layer thing is somewhat continuous between different layers.
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I have Rostock V2 with E3D lite 6, 3 effector fans and stock EZextruder(calibrated).
The filament is Protoparadigm PLA yellow extruding at 200'C. Using Mattercontrol via USB(I tried SD card print and it did the same)