Camera makes noise when switched on and shutter won't release.

My Konica Minolta Dynax / Maxxum 5D is not working. Recently, I started having this problem: The camera makes about 12 clicking noises when it is switched on. The shutter release won't trigger when the button is pressed. The auto-focus, displays and other automatic functions of the camera appear to all work. I was able to get the camera to function a couple of times by shutting it off and turning it back on again. I also tried switching lenses and coincidentally that seemed to work, but now nothing seems to get it to wake up. When I uploaded the last set of pictures I had difficulty with the card, my software (i-photo on an os X Macintosh) said something like " the card is in an unrecognizable format". Then it wouldn't upload the images. I re-inserted the card into the card reader repeatedly and it finally opened and uploaded the ~175 images which came out fine. Both of my 1 gig cards are presently empty of images and I can't get the camera to record to either of them. The general function of the camera seems ok, both of my batteries power it up. Incidentally (or coincidentally), when this trouble began, I had just inserted a battery into the camera to see if it was charged and it in fact that battery was so low it wouldn't power up, but it did light up the LED on the back of the camera. So I charged up my other battery and inserted it and then my troubles began. I had been following the storage suggestions for my second battery, which is to leave the battery in a low-charge state when in extended dis-use. Can anyone identify the problem and suggest a way to correct it? Thanks, Daniel.