I have two burners, the 104(A04) and the A05. The A04 is running firmware 1.31, and the A05 is running 1.21. The problem I'm having is that the A04 will not burn 2x media at 2x, even though it's supposedly a 2x burner. I think my firmware may be the problem, though. I've tried updating it, using both official versions and hacked versions. It keeps giving me an error that the kernal doesn't match. I've successfully upated the A05, so I'm pretty sure I'm doing correctly. Does anyone have any suggestions? I mean, I can always just use the A05, but I only wanted to use it for 4x media.