stroppy, have and ripit, not disputing poor quality I have said so myself, but with G05s it doesn't showright away, their problem is fast degredation. All my G05s, before I knew about this site, worked perfectly after the burn as time went on they got worse.
As the faults seems to be in the same place that is not indicative of the media, this reads to me as something to do with settings. It is the only time I have seen a fault appear in the same place on each disc regardless of brand, from personal experience when doing things for family.
Though scans of different discs will help. Also try a different media to see if it still happens.