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I have been using the swap trick for ages now and have many backuped up games which work great, i recently lent a friend Radient Silvergun and Panzer Dragoon saga which work fine on my saturn but will not work on his, he is also using thw swap trick and has other backuped up games from me which do work, he also ha s the same model saturn (2 with round buttons) any ideas why they work on mine and not his?