New Radio (Frsky x20s) Motors need extremely high throttle to spin

Hello, I have a problem with a Pixhawk 2.4.6…
So as my old Futaba T8j was no longer sufficient, I switched to the radio mentioned in the title.
I have performed the ESC calibration multiple times, and once I am done, I can control the ESCs just as I did with my old radio. They spin up all at the same time. However, the ESCs need a bit more throttle than I am used to. Probably between 10 to 20%. The ESCs are HObbywing 40A ESCs. When I then continue to power down the copter and plug the battery back in to test what I did, the motors did not spin. When I raised the throttle, they each started to spin one after another as I was continuing to raise the throttle.
So I went into the Motor Test page in Mission Planner and performed a motor test. I discovered, the motors need about 20% throttle to spin up reliably.
The battery is at about 15V, 4S Lipo.
Now, with the set spin arm and spin min set to what I think are extremely high values, I get the quad to behave as it did before: Motors spin up as soon as I arm it, and.
I can speed them up afterwards by moving my throttle.

Now I am very confused what the cause of this is, and would love for some input on why this could be.

Greatfull for any help / advice!!