Question about video (from Laguna Seca)

Having seen Kary's video from Laguna Seca, I thought I'd post one of my 1:36s from the same POC event, but something strange is happening that I can't figure out. The lap in question is a 1:36 according to lap timer, transponder and POC records. When I time the video of this same lap, it comes out to closer to 1:40. However, even worse is the version I downloaded to my computer from the video cam. Its time is 1:10 (it's very impressive!!
but highly inaccurate).
Anyone have any ideas as to what's going on here?
Thanks,
John

Anyone have any ideas as to what's going on here?
Thanks,
John