How to change the materials' parameter value, based on system settings?

I’ve created a simple launcher for my game that allows players to change default controls and adjust graphical settings, but I also want to add an ability that will allow players to turn on and off the realtime reflections. Inside all my master materials I have a True/False parameter, called “RealtimeReflection”. If it was set to “False”, material will output a generated by me cubemap instead of realtime texture. How can I implement something like this?