Apple Logic Pro /LogicExpress Discussion

Hey, I'm tracking my band to a live performance - recording them one at a time playing along to an older recording.  Everything went well until the last instrument (banjo), which recorded at the wrong tempo (?!?).  How is that possible?  I was there, and he played in sync with the other recordings perfectly through the whole song.

I know that if you change the song tempo (which I did not do), the regions move around relative to one another, but I don't have many regions.  All tracks consist of one or 2 audio files, and when I play any one of them alongside the banjo, even synced to start playing at exactly the same time, the banjo drifts further and further behind.

I have no idea how that's possible.  I even confirmed that they are both 24 bit and 44.1k, so I am really baffled here.

Any thoughts?

Gregory