Yeah, I got the same problem here. I'm playing on a laptop right now because i'm at uni and I forgot my mouse, so I'm using my touch pad. And for whatever reason whenever I try to scroll up or down, the game insists it automatically scrolls to the very bottom or very top.
I've even tried using the arrow keys and I've even tried using the scroll bar. The arrow keys change selection to whatever you can currently see, then when it goes off the list, the selection disappears like it's been deleted and no longer makes the selection noise. And the scroll bar, how did you mess this one up, ubi? When I try selecting the scroll bar, it insists scrolling back to where it last was - in this case the top or bottom, because I can't even look at or change the 1/3 of keybinds at the middle of the list! Even clicking to a new spot on the scroll bar scrolls back automatically to the last spot and hold-click does exactly the same thing.
Obviously it seems ubi's intention was that this game was not meant to be played on a laptop, but I think such a fix deserves attention to those who prefer using the scroll bar in game!