What is the difference between the detect and force 24Hz in input settings?
Some NTSC DVDs are marked as 29.97 frame rate, but in fact they are 23.97 progressive. So you get a message said “Too much sample try other frame rate”. If you select “detect prog 24Hz”, Xilisoft DVD Ripper will detect that type of DVD. This detection may not work so you have to check “Force 24Hz” if you think that this detection has failed and set output frame rate to 23.97. If the DVD isn’t 23.97, you may get the same error. Then please try other frame rates.