Since 0.9 i more often encounter a problem with plotting paths into other SOI, not only on the boundery, but already at setting up the maneuver node, by continuously changing the prograde delta v i cover a region that should in its entirety lead to an encounter (change of SOI), and it shows the encounter paths for some values, but in that whole spectrum of delta v (lets call it v_min to v_max for the encounter) there are regions where the shown path flickers between "orbit around kerbol without encounter" and "path before and after the encounter", fast forwarding to the SOI change usually leads the path to be resolved into an actual encounter, even if the flickering effect stopped on the "no encounter"-version. This is badly conveyable in screenshots but maybe i can capture a small vid of it later today. This behaves like a precision problem, but as i described, it is not bound to a particulary hairy maneuver with 0.1 m/s making the difference of encounter or not.. its a range of several m/s where it flickers between the states (even after stopping ship parts movement with hitting fast forward)