im leaning towards it being a save state issue or there is a problem with your disc/image. so what are you playing the game from, the disc or an image? and even if they are not directly related to the problem here, i highly suggest loading from memory card saves from now on.
the reasons for this are somewhat technical and i dont think getting into the specifics of it will help much here but the main thing you need to keep in mind is that save states are unstable and can lead to a wide range of problems, you will be saving yourself from a great deal of trouble if you do not use them as your primary saving method.
btw please make use of the edit button instead of double posting.