I have had my 104 since August of 2002. I downgraded the firmware when I go it to version 1.33 so it would burn at 2x. A few weeks ago the 104 quit burning dvds. It kept saying "power calibration error" when using Nero. It would not work with any of the other four programs I tried either. I then upgraded the firmware to 1.40 and tried that. Same problem in Nero at 2x. I tried burning at 1x and it worked. It does the same thing with different types of media. So does anyone have any idea of what the problem may be?