Look at the note in the event editor. See if yields a clue. Look for such things as another event that may be interrupting the note off command, such as a program change occurring before the note off message is sent..or a stray controller event..
You did not mention if it was the same note each time.

Another thing to try, save the seq under a different name. This may be a case of a bad spot on HardDrive, and saving it with a different name will cause it to be written elsewhere..

Just a couple guesses
It is a weird problem.


I do not work here, but the benefits are still awesome
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