There is an issue with a few SKR Pro boards wrt endstops. This issue is the only thing I can think of that matches your symptoms. Assuming this is the cause of your choices are:
- Replace the SKR Pro board
- Disconnect the LED for the endstop(s) by removing the LED or cutting the traces.
- Add pullup resistor(s).
Most people who have this issue elect to add pullup resistors. These can be added by soldering the resistor directly to the SKR Pro board, or by adding the resistor to the wiring connection.
Here is the first topic where the issue was identified.
Here is a topic where the resistors are soldered to the board.
Here is a topic where the resistor is added to the wiring.
As for other causes, you might try flipping the plug at the control board to reverse the polarity. This shouldn’t make a difference, but there was one topic where was supposedly did.
#define ENDSTOP_NOISE_THRESHOLD 3
If this is an SKR board issue, changing this setting might mke the issue worse.