my pre record doesnt seem to work either, i dont know how anti dither and record works either. all my videos seem to play back with 6 seconds of pre record ,then there's motion, then it cuts off, total time is around 22 seconds. i do know, i get about 30 snapshots of absolutely nothing and maybe 1 of a vehicle that passes by. if you figure it out or find any info on this let me know.