I have copied quite a few DVD's now on Ritek x4 unbranded DVD-R's and they all seem to have copied fine. Some DVD players won't play them, but I'm not that bothered cos they work in my player. It starts off playing fine but if I try to skip through the chapters too quickly they just crash. They also always seem to crash half way through the DVD (When it changes direction). I then have to turn the player off and start again. Basically I've never watched a copied DVD all the way through and it's starting to annoy me. It doesn't do it on original copies so what could it be? Thanks.