jm22- remember, when the beatles were looping tracks, it was done on tape. and if anyone has ever tried to sync up tracks from tape that haven't been sync'd through some sort of control code, know it's a nightmare. I say that time does vary on tape, quite a bit, actually. So while, they may have been using state of the art 1965 gear, it was still recorded on tape machines, wich do not keep time up to current standards. So i'm thinking there could have been some variences introduced in the loops' playback.