Just a guess at this but I
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Just a guess at this but I’m thinking that it has to do with the software that creates the DVD structure. Software is supposed to create DVD structures based on the DVD spec. And although the software may create a playable disc, the structure may vary. If the actual script codes are not right, some players may not know how to interpret them.
Vegas is a name I’ve seen for some time but never used. I would have to believe thats its a credible name and there shouldn’t be any issues with what it creates. Has Sony responded with the fact that the same disc created with another application works fine on the players in question?