Multiple Xbox Controllers - Trigger Axis Always Return 0

This seems to be a Unity problem and searching around I have found other wonkiness resulting from multiple controllers, but not this issue specifically and no solutions.

When I have one xbox controller connected, the triggers work flawlessly. As soon as I have more than one controller plugged in, all triggers will only return 0. As if they are not being pushed at all.

I know my controller buttons are mapped correctly. The joysticks and face buttons all work for up to four players. My triggers are named LT_X, RT_X where x is the player index. The settings are identical for x 1 - 4 (as far as gravity, dead, sensitivity, type, and axis. Joy Num is set respective to x).

I get no errors from GetAxis() using any of the trigger inputs. But when there is more than one connected, even if the others are not in use, GetAxis() will not return non zero.

Is there any known fix or workaround for this?

The inbuilt Input system is notoriously rigid, and recognising distinct Xbox360 triggers, in particular, can be tricky to deal with. Most people use InControl, ReWired, or another asset when handling anything above a trivial input scheme.

However, this week Unity announced Developing the new input system together with you | Unity Blog which I suggest you try out and provide feedback to.