About Controller Calibration

[Shinichi]

I am playing with RF9.5S helicopter hover training.
The other day, the controller was behaving strangely (the rudder was moving on its own), so I calibrated the controller.
However, the rudder stick does not reach the 50% figure as shown in the picture, regardless of the stick being in the middle.
Do you know how to solve this? If you know, please let me know.

 

[flightengr]

Rudder trim, perhaps.
Which controller are you using?

 

[Shinichi]

Rudder trim, perhaps.
Which controller are you using?

I use the dedicated controller Spectrum Interlink DX.
However, inexplicably, this is happening with RF9.5S, but with RFE it works correctly as normal.