I got this LiteON DVD burner last year. But since new, this drive has been producing weird DVD burns. The written DVD has deeper and lighter rings alternatively. Very much like the second picture.
But the drive doesn't fail in the writing process (except 2 cases out of 50.) and reads normally. But the read graph is very unusual.
Please refer to screenshots of the same DVD read by the LiteON iHas124 burner and an ASUS (which people say is a rebadge of the same LiteON drive in question):
Why is this happening? Is the drive corrupt?