I use DVD Shrink to re-author or compress an original DVD then writes to an ISO image file. I then use DVD Decrypter to write the image file back to DVD. I have started experiencing a problem. I recently burnt an ISO of a movie to DVD and tried to play it on my Sony DAVS400 system - it errored that the disc was dirty. I took the same disc and tried it on a lower spec machine I have in another room and it played fine. Is there some sort of flagging on the disc that the lower spec machine does not require to play whereas the higher spec machine does? I am using an LG dual layer +/-RW DVD burner with -R discs If anyone could offer an explanation I would be very greatful.