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So, SNES Donkey Kong Country 3 keeps deleting my saves. First we noticed that the game has erased one of the earlier saves (game is my cousins, I'm just borrowing it) and one night when we were about to try again the second to last stage the game had erased our save. Well, we started again and got as far as before with no problems in saving. My friend finally got through it and I was so happy that I accidentally ripped my controller off SNES. Of course SNES didn't response and we had no option but to restart. And again the save had been deleted. This has happened few times before, when the controller comes off, the save erases itself also.. The weird thing is that there is one of my cousins saves that have survived through all this so I think it can't be about the batteries... I have a PAL version. I don't know if it matters.
Does anyone have the same problem and/or know how to fix it? Or at least where's the problem? My SNES doesn't do this with any other game, just this one.