Yes, i think it's not necessary a specific setting, it's rather the limitation which comes with the used sensors (camera's). Even though they already made huge improvements on the whole tracking stuff (when you compare quality from last year with today) they still have to calculate everything on software side at the moment, which has unfortunately some limitations, especially when it e.g. comes to depth or "covered/crossed" hands and so.
But cool, glad that poking at least worked. Because usually they just recommend on single objects to use either poking or grabbing. Or if having both, then there should be a specific area where you only can grab. But i tried for phone and tablet to combine it, think that makes more sense (from user perspective).
When it jumped randomly, could maybe also happen, that your room was a bit dark? Unfortunately currently this whole hand-tracking stuff is very error-prone if the room is not well-lit.
