Thanks for your reply. The first note in question isn't very long - less than two seconds in fact. And it strikes me as somewhat odd that a sound continues even if there was a clear note-off command. Seems to be a bug to me. Also that a note starts with a legato transition when there's no note-overlap.
It can be worked around through editing the samples chosen (e. g. switch to a long detaché for the first note) and the cc data (draw a dip at the beginning of the second note so the legato transition plays back more quietly). But it's more time consuming than it would have to be. If there are plans for an update it would be nice if this could be looked into.