Nothing to do with shrink it only uses the data its given,id look more to the discs you use (poor quality) or dvd player (perhaps getting old,perhaps dirty laser or only reads certain types of format say reads dvd-r & not dvd+r) to being the cause.

Could be a variety of reasons:

1. Operator error.
2. Brand of disc incompatible with player.
3. Format +R vs -R type.
4. Was disc finalized.
5. Update firmware.

The list can go even further ...

Need more info !!!

What is the error message ??

I TIOTALLY AGREE WITH ALL OF THE ABOVE I HAVE BEEN USING SHRINK FOR 3 YEARS IT WORKS PERFECTLY