LITE-ON DVD+RW SOHW 802S CANT BURN CD-Rs

Hi im using a Lite-on dvd+rw burner as mentionned in the title, and I cant burn CDs. It can read CDs though(blanks too). I bought a hp media center pc that comes with this drive. I have made recovery disks with it too. I havent burned anything except the recovery disks. My drive couldnt burn dvd-r too before i flashed it with a firmware(now i can). But I would like to know why my drive cant burn CDs.

thank you