Sorry Glenn, for not understanding your response at all.
I'm not talking about any hardware.
I discovered, that the C172 aircraft modeled within X-Plane 11.30 shows significantly more drag tham the same aircraft modeled in 11.26. The way I came across this is a cross check between both versions: I flew the exactly same trajectory (straight glide path with defined glide angle) starting from a saved situation with the engine off. The 11.30 version shows significant lower speed (KIAS) than the 11.26 version. In 11.30, the chosen glide path cannot be maintained til the end as the elevator needs to be pulled till stalling with the chosen glide angle.
I really wonder, whether this is a bug or some "improvement" in the flight model.
No HW involved.