Hello,
I got AxiDraw SE recently and I love it, it is a wonderful little machine!
But few days ago I did a couple of prints, and there is same distortion happens happening every time I try. Marker is mounted properly, but maybe I’m missing something else.
This is how image should look like:
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But you’ll notice anomalies on the upper part of the print:

I highlighted distortion on this image:
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This is the SVG file I used.
I generate these SVGs by the software I’ve written, but no matter the params I use, plot comes our distorted.
Link for the software:
https://muffinman.io/vertigo/
I’m using macOS and following software versions:
Inkscape
1.0beta2 (2b71d25, 2019-12-03)
AxiDraw Control
Version 2.5.7 – 2019-12-13
Let me know if you need any more info.