https://www.saitek.com/manuals/SST_Manual_En.pdf
Si je comprends bien il faut désactiver Fall Back.
Fall back: By default, any commands that you program to a button in the basic mode
or shift state will automatically be carried over to the other modes or shift states. When
Fall back is ticked, this is the case. You will probably want to assign different
commands to individual buttons in different modes.
To do this,