None of my DVD-R's work in my portable DVD player (Panasonic LV75) although they should do. I even have a friend with the same player and his will play my discs. I am using Nero 6 and there are so many options to do with ISO etc. that I'm wondering whether tweaking some of these may solve the problem. Is there a most compatible set of options that I can choose ? I currently just use the DVD-Video template and accept all defaults. Works fine for all standalones that I have tried...except the portable.