I have a 1213S and tried to upgrade it to a 1633S with the firmware from codeguy’s site. The flashing appeared to work, and after rebooting, Device Manager recognized it as a 1633S, but the drive wouldn’t read any disks – if I inserted a disk, the drive would spin up and the external light would flash continuously, and it kept spinning and flashing until I ejected the disk. If I tried to access the disk during that time, Windows would tell me to insert a disk in the drive.
Has anyone else experienced this problem with this kind of upgrade? Did you find a solution?