Pixhawk 4 , PH4 sbus doesnt work

dear all,
because I´m more familiar with Ardupilot I change today the Software on my Pixhawk 4 from PX4 to Ardupilot. I use the Arducopter 3.7.0 Version from “/Copter/latest/Pixhawk4”

Since then I dont get any connection to my S-Bus Reciver. Under PX4 it was no Problem at all.

PPM works well on the PPM RC input Pin
SBus doesnt work on that one, nore on the DSM/SBUS/ RC input

Has anyone got an Idea?

Thanks
Stefan

Try the Stable version 1st before latest which is a Dev version.

Thanks
Done…
Unfortunatly same Problem

Which brand/type of SBus receiver ?

Graupner Hott with the latest firmware

Would be great to know the exact model and fw version to test, because some of us have Graupner receivers.

@tridge