Hey I may have found the solution! I just went for another try, now not at low speeds (1x, 2x, 4x) but at higher speed. I tried 8x, it was just a guess, cause the DVD itself has 8x printed on it, and when you check the available speeds its from 4x to 10x so I thought 8 is nice in the middle. Anyway, it just finished burning without error! First one without error for me. Dunno if it was luck, will try more later. DIsc is now verifying, I'll update you when thats done.