I have a Contax 645. I have the battery grip for it so I power it with 4 rechargeable AA batteries. The problem: sometimes without any explanation the yellow exposure scale in the viewfinder goes blank. The f/ numbers and shutter speed info disappear in the viewfinder and the whole camera goes blank. I try to press the shutter button but all I can hear is a clicking noise. I keep trying and all of the sudden the viewfinder is back and I can see the exposure, shutter speed, etc. I have tried to change the batteries and replace them with freshly charged ones but I don't think that the low battery is the problem. I have another Contax 645 and that works without problems with the batteries. Did this ever happen to you? How can I fix it? I can't rely on the camera if it just decides not to show me exposure, shutter speed, etc info. It always comes back but some times it takes 4-5 minutes... What to do? Thanks for helping!