Focusing problems with A35 and A55

[Sheean93]

G'day

I have an A35 and A55 both with the same problem. Neither can seem to focus. It seems to think that the scroll under the shutter button is being moved as the shutter speed is constantly changing. I can't access the menu as any menu I open will close almost immediately after being opened. For whatever reason my Sigma 10-20mm lens works fine but my 3 Sony lenses and my tamron lens also does not work.

Thanks for any help