bounce has unwanted space at beginning

I am trying to stripe out a session that I made by importing as OMF from MOTU DP. I need to bounce 7 tracks down to stereo and then load them into a Protools session at another studio. I have deleted all automation, and all fade files. I have put a 2-pop at the beginning of each track, at bar/beat 0. I set the cycle maker from 0 to the end. The session is at a fixed tempo. Each track I stripe out starts just a little bit before 0, between 1 and 2 beats I think. They are all consistent, but the extra material at the beginning is not an exact division of a measure, so it's very difficult to get them exactly right in Protools. I can cut off the begining "by eye" up to the 2-pop, but that isn't totally accurate. Why would this be happening?