Read DVD Problem on some DVD readers

[ararara]

I have a problem vith my DVD backup, on my DVD Reader (an kiss 500) i read all DVD backup but when i use this backup on other DVD readers such as an generic Philips, at the and of a movie the movie stop or go very sleepy.
Always this happen at 2 or 3 to end of the last chapter of the movie.
Anybody have some problem as mine?

[sfheath]

sounds like physical damage to the outer edge of the disk or just borderline media. have you tried other brands?