Mmm I tried the usual places VideoHelp.com and digitalfaq.com neither have any details on the media ID, the latter in fact seems a little out of date now !
I had some of these discs as test discs a while back - check out the burns here, RITEK-R03-02 not the best I have ever seen mate
You can see here that your drive is reporting that it can burn these discs at 6x, 8x, 12x & 16x only. For whatever reason the firmware does not support burning below that speed
Yeah polo is right - no speeds lower than 6x are supported with that firmware on the drive.
6x shouldn't give you any quality issues with decent media anyway