Filtering problem in a 2d game

Hi everybody!
I’ve got a micro problem in my 2d game for iPad. The game is full HD, so I turn off any filtering modes, mipmaps generating, any compression and I use ortho camera. The size of the image is exactly how it was drawn. The game has got a zooming from 100% to 120% and scrolling in any directions. So the problem appears when I scroll my scene - my images are being pixelized, like I rotate them. They are flickering. But I only move them, so they suppose not doing that. I can see the pixels in the image changing. Particularly the problem can be seen while 120% of zooming.
I was playing with filters and texture rendering, but I’ve got nothing. I just want to understand why this is happening, for example it can be an iPad issue?

My guess is that you're not scrolling in precise pixel-sized increments, so at certain scroll values it's getting sampling errors. For example, if the image is scrolled half a pixel to the left, then screen pixels map to the edge between two texture pixels, and it's not sure which to use, so it would create artifacts like you describe.

Also, if you're using just one 100% texture and scaling it up to 120%, rather than using separate textures for the two, this is going to create more of the same artifacts. If you need to freely scale the texture up/down you might have to turn mipmaps back on; you'd be abandoning pixel-perfection anyway, and that's what mipmaps are for!