I have the same problem here!!
the program detects my DVD+DL media as 4x and 6x, but the real max speed is 2.4
I select 2.4x on the program but it writes at 4x.
I think that the program can't force lower speeds, I tested on 2 drives, same problem on both of them.
the result is a broken DVD.
sorry I have no log saved, and I don't want to break more DVD+DL, they are too expensive.
is there any way to real force the 2.4 speed??
thx. a lot and sorry for my English.
EDIT: ok, dam it, Nero suite detects the same write speed.
so, I think it's a firmware problem.
but, in DVDinfoPro appears that manufacturer Speed is unknown, so the speed is defined by the Drive, on an older DVD-Writter appears at 2.4 Speed, but it's the max speed for the DVD+DL supported by the drive.
Can I force the speed? because if I select 2.4x the new drivers writes the DVDs at 4x.