Originally posted by Clavius You really keep all your video stored on your camera forever?
With no audio samples or knowledge of your application or goal, it's difficult to give constructive help. Apparently you've determined the clicks aren't in the original recording? This cable would be the best way to determine this, I think, since no software is involved outside of the camera's firmware. For that matter, are you running the latest firmware?
I haven't encountered this problem yet. I use Sony Movie Studio HD on Windows. It's free to download a trial. It also takes you through the whole burning process successfully - DVD or Blu-ray. It's much less expensive than Final Cut Pro, and more capable than iMovie.
Without researching it, I wouldn't be surprised if most of the ~free apps you've tried are using a similar conversion engine. Not worth the trouble unless they're giving you a specific benefit.