Even though there have only been two issues. The autofocus on my 5 month old 70-200 failed, was replaced under warranty. Batteries in my 5DMkIII would drain overnight if left in. Turned out there was a short in one of the terminals, fixed under warranty.
Well, been having a problem with the 100-400. When I half press the shutter button to focus, focus won’t lock, and the aperture reading would change from whatever it was set to 00. (ie set to f/8.0 and when the auto focus hunts it jitters and goes to 00). I did all the at home remedies/tests: cleaned the contacts. No joy. Tried it on different cameras.. still happened.
So, I called Canon Australia, spoke to Tech “Anthony”. I told him the symptoms, what I had tried to remedy it, and that I had found several forum threads about this problem. He took my information, emailed to so I could send him the link to DPREVIEW thread about this. There are others, more recent, but it’s a case of repetition. Different people, different forums, saying the same thing.
So, he said this is marked as escalated, and will have ti looked into right away. Then he asked me for information, and when I gave it, he said “Wow, you’ve had a rough run of luck” I’m hoping this can be rectified. It’s an annoyance, not earth shattering… just annoying.