I think it's the setting called "grid settings follow grid visibility" which is in the box you get when right clicking the snap "magnet" :) I would try the other feature we have which is if you set the top right pixel box to something around 70 (depends on screen res) and then set the snap to about 32. This then gives you a higher grid setting as you zoom in and a less detailed grid as you zoom out. It's worth trying, I find it works really well for most things, for moving in detail when your zoomed out you could use the new nudge box and it's related key commands :)