Dvds not burning properly (rings)

[zukazamaami]

I have had this sony optiarc dvdrw ad-7240s for almost a year now. I dont burn dvds much. when I bought it I had xp x64 installed and was able to burn a dvd using active iso burner at 4x speed just to be safe. after that moved to win7 x64 and over the year filled some CDs without probs using the inbuilt burner. this week I decided to backup some data on dvd discs and got some good quality 16x dvd-Rs. so the problem is I have tried burning by moving folders into write folder, by creating and burning iso, by using 3rd party burners, even upgrading to lastest firmware but I always endup having a defective burn. the data side of the dvd gets filled with 7-8 rings. the contents are visible when reading them but ofcourse the files dont work except for some small sized ones. No matter what the speed I set there happens a burning error and burning aborts, sometimes there is even no error until verfication where it fails to read. drive reads DVDs and CDs fine though.
I have run out of options, what else should I try to fix this? could the drive possibly be defective? if so I need to confirm it quick as its warranty will be over by this month.
I have attached an image of a dvd after burning an ISO using Imgburn. took over 11min to complete at 8x and strangely it gave no errors during writing process..

 

[zukazamaami]

anyone?

 

[hang-the-9]

That looks like an issue with the DVD drive, I don't think I have seen anything do this to a disk, expecially after only a single image burn. Even when you add data to a disk it only adds a very thin line between data tracks.

 

[jefe323]

i've never seen anything like that. i would recommend getting a new DVD drive (considering how cheap they are these days...)