midi end of song doesn't match event listing

[PrimeAuralAudio]

Here one's for you. I imported a midi file into ProTools 6.7. Played it and recorded the output of my synth into a stereo track. All worked well, UNTIL I bounced to track. My bounce to track output is about 50 seconds longer than the recorded track and the midi event listing. I've tried to select the overage and delete it but no luck. I've reviewed the midi event listing and the last events end at about 4:30. If I used the transport buttons to jump to the beginning and then to the end of the song, it always goes to about 5:20 instead of 4:30. Yes, I can go back and reimport the track and trim the silence at the end but I shouldn't have to. Anyone know what I'm missing here?
thanks,
PrimeAural Audio