Waveing vertical planes

Can you please help me to solving problem with vertical lines on planar model?
I have found someting about acceleration. Default was set on 6000. I have lowering to 400 but this doesnt help.
And also it doesnt seems like infill error.

Thanks you all.

This effect is inherent to the 3D printing process. The motors do not move smoothly but in very small increments. If you print a straight surface slightly on an angle you will see this effect. Also on spherical objects this effect is sometimes visible. It’s a bit like pixels on a computer screen.

The second photo looks like normal behavior but the first one has this effect quite severe. Did you print it on an angle (and by that I mean to draw the straight line did the X and Y motor had to turn simultaneous?)