Playback problems with Sony dvp-ns708h

I recently purchased the sony dvp-ns708h upconverting player the problem i have is with PAL Dvd's. I use a program called convertxtodvd to convert these files from PAL to NTSC to be able to play in my dvd player. Now the problem i have is that they play fine but every once in a while there's some sharp lines going through the picture. It's just with this player that it does this my other 2 different models an older sony and rca play the movies flawlessly. I was told that sony is clamping down on movies other than region 1. My older players seem to get around this but the sony dvp- ns 708h is not fooled. Can somebody please help me fix this problem. Is there a way to modify this player to play all regions.