There are two issues here, the first of which is solvable: input sensitivity by default it too high. Instead, set the Flick-It sensitivity to its lowest setting and you’ll have greater control. Your pops will be lower and slower at first, but it’s better long term when you’ve adjusted to it.
The more intractable problem is that laggy server response (typically from greater player load) sometimes causes twitchy input detection and response, knocking the physics off kilter in the process. There’s not much that can be done about that, beyond an offline mode…
My pops are already low and too slow, and this game doesn't let me jump onto higher obstacles. Sorry, but I'm trying to achieve higher ollies and jump onto higher obstacles than the developer intended, so I can't change the settings to make me jump even lower... this game is very limited.
