Help with animating icon

I made the frames for this icon in Photoshop Elements 3 and I animated it in Animation Shop. I saved it at the highest quality and it turned out crappy. The background is very pixelated. But I guess it looks like a texture, but it's supposed to be a solid color.

Does anyone know why the background turned out like that? Does it have anything to do with web-safe colors or anything like that? o_O