I have the same problem. It changed a little with the latest update (it vibrates less, but it still can't focus), and it comes and goes, but about half the time I can't use zoom or live focus. It seems to have to do with the secondary camera that's used for zooming. I took it to the T-Mobile store and they said it should be replaced, but this is happening to so many people it makes me wonder if Samsung messed something up in software.
Cycle through all of your camera options. Video, pro, panorama, slo mo, etc. Do that a few times. Mine no longer has the issue. I even took a few photos on each setting to really confuse it! Now, no buzzing, no wavy picture. Works fine with regular all the way up to full zoom.
I am having the same issue - it is intermittent and I suspect that it is a fault with the camera hardware. The aperture seems to be trying to switch back and forth rapidly, causing the jittery feel and buzzing sound. Until the problem is isolated by Samsung, and corrected under warranty, the only solution is to restart the phone and hope it doesn't repeat for awhile. Problem is that, by then, we have lost the opportunity to get our photos.