I'm a bit baffled at why when I back-up one of my dvd's I get a small burn ring and when I do it again with the same burner and disc it is more appropriately larger. Both burns are playable on PC and standalone DVD player so that is not an issue. I'm a bit worried that the disc with the smaller ring may be less effectively burned and in the long run may faulter. I'm using as the burner LG GSA-4167B as an external and Sony 1-8x discs. I'd be very gratefull if someone could offer me an explanation for this mystery.