Burned Karaoke on DVD but songs turned out cut short?

[islandsunflwrs]

I burned Karaoke vids onto a DVD-R in Divx format. When I was done and played it on my Karaoke stereo, the songs were cut short before each of them got to finish. Why did this happen? How can I burn them again and avoid this happening? I did not use up all the space on my DVD-R. There was still tons of space left.