I was doing some test recording with my macro, for a small test project I had in mind, when I noticed the image flickering when I was focusing in and out. At first I thought it was just my eye but the issue was still there when I looked at the video playback.
Not everyone seems to have this issue (but I am not the only one), which make the clip unusable.
While asking around I was suggested (by Matthew Bennett from the Cinema5D forum) to twist the lens a little bit (like if you were going to remove it) to disconnect the exposure contact and tada! It works. I was so caught in the problem that I forgot the most obvious solution. Here is a video of the “proof”, now I just need to redo all my initial takes…