We have a handful of these on service (none on my route), and they all have the same problem, on a fairly regular basis they end up buffered out in the pit or overhead. These are units in different buildings, different cities, different ages, different machines, operators etc. Everybody has kind of given up on figuring out why they all do this because someone heard about some kind of magic software upgrade that they need from Kone. Anybody know about the software upgrade (if it exists) or what makes these units prone to this problem?