unwanted racetrack pattern

Afternoon All.

I recently built a cnc table. I made a plasma table years ago and had no issues, router adds a few more dimensions, now I am confused.

My issue is the cut path is an oval rather than squared corners. I use Kirimoto as my slicer, it shows square corners and the animation gives square corners. Move the file to my cutter and it also shows squared corners in the preview. When I cut, the corners become rounded, exception of one corner where the tool always moves to the next x y z start position.
I am including two photos, one is a cut track as shown on linux the second photo is of a different file and shows the actual rounded corner, opposite end of the cut is completely rounded.

Any thoughts?
 

Went through the g code could not find a g64.
I am running 2.7.15
My photo is too large, will work on that.
THankyou for your help.
I thought of something in kirimoto that might make a difference but not certain exactly how it works yet.
 

Thank you Tommy,

I now get all four square corners as shown in the cutfile
much appreciated.

David