Light and dark bands on the 'burnt area' of a DVD. Why?

The Tiger

Honorable
Aug 30, 2013
222
2
10,715
I just purchased a LITE-ON DVD writer. Whenever I burn a DVD using Nero, and look at the DVD after completion of the process, I find randomly placed 2-4 mm wide circles in the 'burnt area' of the DVD. These circles are lighter than the rest of the burnt area, but deeper than the unburnt area.

The verification process completes fine, though. This problem is restricted only to this new LITE-ON writer, not for my other ASUS and Sony writers.

I'm using Verbatim AZO DVDs and a writing speed of 8X.

What's the problem? Should I send the writer for RMA? Will this affect the archival life and data integrity of the DVD? My data is critical.
 

The Tiger

Honorable
Aug 30, 2013
222
2
10,715
I can't return the writer. I got it for a steal deal, and I'm stuck now. Only thing I can do is go the service center.

The verification process succeeds and Nero Disc Speed reports ~90% of disc quality. Should I still be concerned or ignore the rings?