Kubla generating multiple lines when exporting to AutoCAD

Whenever I generate a CAD file from a Kubla project and it doesn't matter if its just from the existing base or from several levels, I always end up with multiple lines of the same contour line, which gives me significant issues with the CAD software I use.  I've tried using OVERKILL on AutoCAD to remove redundant lines but this doesn't seem to work.

Anyone have any tips for generating contour lines with a single line rather than several?

Thanks!