sooooooo im hopeing you checked this already but do you have a active beacon that could be doing it to you. or a artifact in your inventory
Nope and nope. The only thing that might be applying anything like that is either my normally enchanted mage armor boots (which have haste), and the globetrotter's sash from the quest book and Botania, which didn't have the infinite jump buff when I first put it on.