Also if this happens again stop the playback and look at the track in the piano roll view (PRV). If it is a MIDI track problem there may be one long note throughout the track. Also look for overlapping same notes as has been suggested.

As John said what sound source are you using? If the polyphony setting is lower that the number of notes being sent to it it may be missing the end of a note.

When you are at the checkout line and they ask if you found everything say "Why, are you hiding stuff?"

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware