Ok, willno2's drive is fine, what about mine?
I used a noise removal tool on the sample I have recorded, there are same artifacts, but I think it is possible to hear the noises I am concerned about. I have attached 70KB mp3 file.
First 15 seconds of the record is tray loading and recognizing DVD+R media, then 12 seconds reading at ~4x speed, there are these weird noises most obvious, then 6 seconds reading at 10x speed and stopping the drive.
gsa-4120b_noise.zip (70.1 KB)