The problems with double sided, duel layer Universal DVD’s have become legendary over the past four or five years for having serious issues with there authoring. There are a lot of releases that seem like about one of every four copies are messed up. The really bad side of this is that it might only be one movie or TV episode out of a large number so it takes a while to get around to them all. Some of the ones other then the Hammer set that I’ve either experienced or heard about problems with are SeaQuest Season one, Airport terminal pack and Kolchak complete original series. They seem to be back on the ball but you can still get burned with some of there older releases.