Sony AW-G170A cannot read UDF disks

[qanda]This thread is about the Sony 18x High Speed AWG170A DVDRW Black. Click here to see full specs[/qanda]My sony AW-G170A cannot read UDF 2.0 Disks written on the same drive however the disks are working fine on other drives.I have tried to resolve this problem by flashing the latest firmware(1.75) without any luck.
I have checked the disks written on this drive on my AD-7240S dvd writer which is on the same machine and it reads them fine…so plese help me with this…

P.S. I have windows XP SP3 and Vista.

Welcome to the forum.
Have you tried reading other types of discs, pressed DVD-ROM for example?
You could try cleaning the lens, but i have doubts that would cure the problem, as it could be the laser assembly is faulty.