Apparently there is a problem with these Liteon models which were released late last year. While burning cdr's, there would be an instance that the burning process will end with an error. After that, the drive would no longer read cds, it can only read dvd's.
Bro where did you get the info? I have assembled 4 pcs for my friends with 1693s models last year, and none have resulted with the said issue. Mine is just brought last november and got no problem as well.
'Been a lite-on user since 2003, from 24x cdrw era to dvdrw 8x era, and so far I did'nt get any defective drives.