I lost RC input from 3.9.x to 4.0.x

Hi guys

Something very weird happened.

I have a vtol that was running arduplane 3.9.8 with a VDC15 here

So it’s simply a Taranis, connected to a X8R, connected to VDC Transmitter than VDC Receiver to Pixhawk 2.1 RCIN.

It’s working perfectly under 3.9.8, but once I update to 4.0.1-5, I don’t get anymore signal " nothing is moving under the radio calibration tab in mission planner. And if I connect the X8R directly to RCIN it’s working under 4.0.1-5.

I will try a “blank” parameters, on 4.0.5, but if you have any idea do not hesitate to share

Thanks

Benjamin

Edit : Ok, I tried arducopter 4.0.3, no luck, but it’s working with arducopter 3.6.9