i will expain everything from start
my drive was working fine just for curiosity i used eeprom utility.
i used eeprom utility and did a reset of HT and Learnt Media
[Note:without taking a backup of eeprom]
after that my drive stopped reading some of my dvds.
it was still able to write dvds ,cds very nicely.
2:i crossflashed it shm 165p6s MS0R using stock firmware to fix the problem.but no use.
3:i crossflashed it back to dw g120a using stock MYS3 .
and then flashed it with official mys6
still some dvds were not read .
i took a backup of eeprom and kept it safe with me.
5:i also used flash Flash_Utility-3.0.2 i took a backup of dw g120a.
i got mys6.bin in safe with me.
6:i used eeprom utility crossflash option .then i clicked upgrade drive.it showed a dialog with to option 160p6s and preselected 165p6s.i said ok to 165p6s and continued.
7:i used flash utility and used shm165p6s bin firmware ms0r.bin.
checked the update boot code option and did a flash.
8:i inserted a dvd and used DVDinfoPro info button to see media info
it gave a message that my drive does not support such a feature of reading MIDs.
9:i used eeprom utility and did full reset.i used flash utility and used my MYS6.bin from safe and i flashed using flash utility and also selected update boot code option.then i rebooted.then i used eeprom utility and restored my eeprom from safe which was taken in step 4.
after reboot i inserted a dvd an used DVDinfoPro it gave a message that my drive does not support such a feature of reading MIDs.
from that time onwards my drive is not reading MIDs.
10:bought a sony dvd-r to try burning.but it contantly showed a green light for few seconds and failed to detect the dvd.
current state :dw g120a MYS6
ony reads CDs and DVDs .no writing ,no MID detected.no blank cd dvd detected.
its like a DVD-ROM now.