What's wrong with my 451s, no cd/cd-r media can be used

I just found my one year old 451s cann’t burn and read any cd-r(including Kodak,TDK, even own Liteon media) cd,vcd. But I can read and burn DVD+RW without any problems.

Detail with my burner:
451s@832s with CG5G( But I believe I have the same problem with the original firmware gsb6)
BTW, I connect my 451s to 2nd master,SONY CD-RW CRX100E to 2nd slave.

If anyone can help, great thanks

I ran into the same problem last week. All DVD functionality was enabled on my drive, however, it fails to detect, read, write, or burn any CD media. I updated the firmware to GSBC via the LITE-ON download page, no mods. After that didn’t work, I backed up my EEPROM and Firmware with several different utilities, and proceeded to experiment with different firmwares and programs until I killed my drive with MTKFLASH(no power, light, or tray open/close functionality). I have hypothesized that the problems stemmed from the fact that I updated from within Windows XP to begin with, and then when I used MTKFLASH in DOS, both the EXE and the BIN were accessed from the floppy instead of a FAT-formated harddrive partition. I’ll keep trying and post any results I have. I have been rather curious about the six pins on the back of the drive, all the way to the left. They look exactly like the Master/Slave/Cable Select jumpers, but there is no markings detailing their fuctionality, nor can I find any documentation regarding their purpose. Any ideas, thoughts, or facts would be welcomed.

I don’t believe it is the problem of firmware.
I found this problem before I upgraded it from original firmware gsb6.