exporting sketch as dxf results in extremely jagged lines

Hi,

I'm trying to export a spline sketch as a DXF but the result keeps ending up as a horrible mess (see image below).

A little more info:

I need it as a DXF to work with our CNC machine.

The machine only seems to understand the DXF if it is saved directly from the sketch after doing spline tools > fit spline.

If I extrude the profile and save the face as a DXF then the lines become smooth but then our CNC machine doesn't understand the file so this is not an option.

I have tried every combination of end point merging, spline export options (splines or polylines).

Any help would be greatly appreciated!

SolidworksImport/export