Gsa 4163b problem

Got a temp. 4163B. Flashed it with A105 but it does not allow me to write to MCC004s and MCC03RG20s with 12x. When I open the fw with MCSE the speed is there.
In nero cd/dvd speed I see those speeds: 4x, 8x, 8.0x, 16x, 16.0x
In nero burning rom only 4x, 8x, 16x are allowed.

Any ideas why is that?

read the LG DVD FAQ, Q36