I was working on a project that was started in 6.05 using 6.5 and one of the tracks started arpegiating . After a few minutes of troubleshooting (with my client right beside me), I found that a midi plugin “apache” had been inserted in the midi track rack. I never use midi plugins and this has never happened before. Even after I removed the insert, the track still missed notes so I moved the data to another track and everything was back to normal . Very weird…