[Tested in Input system 1.9.0]
Avoid causing the Input System switching control schemes each frame when using the "Auto-Switch" feature.
If you wish to read input from more than one device concurrently there are a few options.
You could create a scheme that contains the devices they wish to monitor, then use an action map with action bindings that are configured for use in the control scheme.
This will avoid switching between control schemes when input from disparate devices is processed in-game.
Alternatively, if you do not specify a control scheme for an action binding then it will be available in all control schemes.
Think of the "Use in control scheme" check box as a filter - if one or more schemes are selected this will have the effect of excluding this binding from other control schemes.