Cheloo, did you manage to solve your problem?
I too have a LG GDR8163b drive and it has the same problem, it perfectly reads dvd's and original cd's but not backup cd's. The drive is brand new, the version of the firmwire is 0L23 (the latest version I think). It doesn't even read the discs written with my 4163 drive, LG blanks.
When I put a disc in, it tries to spin it and makes a strange sound, as if the reading head goes from one side to another;after a few seconds it stops, and when I try to acces the drive it says "Please insert a disk into drive E:"
Are there any other firmwires compatible with this drive? Maybe it's a firmwire problem and using one from another type of drive will solve it...