When I'm changing the control settings, if I press "m" for instance, since it's already bound to "mute", that will unbind it and whatever I was in will be set to "m". However, it will also toggle mute. Easy enough to get around, since pressing "m" again before hitting OK will un-mute, but it would be better to not trigger mute, or chat, or the like when in the middle of changing that side.

Related side note - ESC on that screen would ideally give you a notification that your changes are being discarded (if you've made changes). Or give you an accept/discard prompt.