RC Fail on the latest betas


My configuration:

Matek F765 Wing
FrSky R9MM

On early versions of firmware 4.1, No RC Receiver messages often appeared, this did not affect the management in any way. With a certain version of this firmware, instead of this message, the FS mode began to turn on via the throttle channel. The receiver is connected via the FPORT protocol. I tried to switch the receiver to the SPORT+S BUS mode, FS does not turn on in this mode. But if you look at the log, you can see that the data on the channels sometimes take random values. I also tried to change the receiver to X4R, this did not change the situation. The behavior remained the same.
Flight logs are attached:

Is there someone using the same configuration of the flight controller and receiver?
I want to understand whether to look for the reason from me or it’s a software problem.