Generally the video project setting for typical NTSC rates have to be 29.97 or 59.94 depending the source clips or it is absolutely usual to get sync/speed iussues using projects settings with 30/60 rates. The 30/60 rates should be used exclusively to create graphic animations or any content PC generated to be run in all PC/MAC/linux enviroments for applications like MS Powerpoint and to be sure to get always a smooth motion. The Dv Encoder is targeted to encode video and could support only 23.976/25/29.97/50/59.94 project rates.