the first thing to do is backing up the eeprom and the firmware.
for an eeprom backup, you need this tool: http://codeguys.rpc1.org/utilities/EEPROM_Utility-3.3.3.rar
start it, choose the right drive and click on backup eeprom. it will create a 1kb file, put it in a safe place.
read this thread for further infos: http://club.cdfreaks.com/showthread.php?t=112103
to backup the firmware: http://club.cdfreaks.com/showthread.php?t=83294
choose the right drive, select backup, choose a filename and press start.
now you're ready to crosslfash the drive with the 832s firmware: http://codeguys.rpc1.org/firmwares/dvdrw/832S.CG5J.patched-cf.rar
unpack, run the flasher and flash the correct drive.
after that, you should run the eeprom util again and click on "Reset Learnt Media" as the 832s firmware uses another learning space.
the eeprom ustility and LtnFW can restore your drive if you're not happy with it after crossflashing.