okay that is odd.

Not filament as areas on the same layer aren't effected.
unlikely to be calibration if the same areas are effected after moving.

So it's down to a design and slicing mix.

Given those parts are slightly wider than the rest I'd say it's an infill issue.
What slicer are you using. Also how wide are those parts and what diamater nozzle are you using.
Quite often if the width of a part isn't exactly divisible by the nozzle diameter, the slicer will use extra 'filling' between walls and that can effect the surface appearance.

I'd pretty much come down on design and slicer for this one.

So what infill settings are you using ? and how wide is the part and what nozzle diameter (and bead diameter - not usually the same, bead diameter is usually larger than nozzle diameter) are you using.