Hi Rok,
Compared to which version do you experience this?
In version 2.15 we improved CAD snapping speed. We changed the point algorithm so, that when you start the CAD up, some background calculations are made, that help speed up snapping. Before in version 2.14, background calculations were made every time when you rotated model. Since 2.15 background calculations are only made when you display different point-clouds or meshes.