You guys are geniuses! Went back through with all you'd noted, found a few previous floating pitch bends that had not been zero'd back out. So I guess it had floated off from there. I put a zero pitch bend controller in after each of the offending events, and it seems to have fixed it.
What I don't understand -- prior to correcting this, when I closed the project then re-opened it, moved NOW time to mid-project and started from one of the mid-track points without passing any pitch bend, I was still getting the errant pitch. Shouldn't it have started playing at that point without acknowledging a pitch bend prior in the midi track that it had not actually played? Or does the audio engine look retrospectively and play as if everything prior had actually been played?
Thanks for the help!!