How do I fix issues with Xbox Controllers not working properly in both Engine and EXE?

This issue is at least partially two fold, and is sort of two problems in one, in some ways.

In the game I am developing, I am using up to 4 controllers on the client side for a 2-4 player party game. When they run, they work well, but there are control scheme issues, and have been in various forms from day 1. I've tried to fix them myself, but am out of ideas.

In the Unity Engine itself, the controllers will work with intermittent success between devices. On the computer I usually work from, they often run fine, with little issue, and have on several others, albeit less consistently. However, on the machine I am testing them on today, the controllers don't appear to register within Unity at all, even after unplugging and replugging, restarting Unity, and even restarting the computer itself.

Meanwhile, when the game is exported to an exe, the controllers are almost always functional, regardless of machine (including the one i'm on today), but do so intermittently. Whilst the d-pad and left stick, which both have inputs assigned to them, work completely without fail, the face buttons (XBYA) never work as intended, having to be rapid tapped heavily to get any kind of response at the best of times, which is a problem when they're required for both the game menus and in-game functionality. I can't tell if this is because of an input delay or something else, but i'm leaning toward the latter.

If anyone has a solution to either of these issues, preferably as quickly as possible, i'd be very grateful.