Need help with veird slicing results

monza64

We have a strange problem with our slicing at home. Have had this Vertex printer for many yaers now and is using Slicr for slicing.
When i download files from any source on the net the slice comes out perfectly round but when my wife draws a round object in Inventor the object becomes faceted when i pick it up in Repetier. The number of facets seem to depend on the diameter of the object.
In her computer the object is round but when i pick it up it is faceted. This just started a week ago, before there was no problem.
Since downloded objects behave perfect i guess its not my computer acting up.
We have tried both stl. and obj. formats
Any ideas from someone about this ?

Repetier

The stl/obj format have no circles so on export from inventor they get converted to triangles. So it depends on the export settings in your cad software how many segments a circle get. You see this already when you view the stl file. The slicer just uses the available triangles. So the problem is purely cad export settings.