Here is another arm cracking theory? How many of you guys with cracking are using a case, or backpack? I have noticed some of these are tight fitting, so pushing them into a tight backpack, or case will cause stress on the arms and may even flex when pushed into a tight case, or backpack. I know with my Phantom 2+ the foam cutouts where just to tight and had to widen them so I was not putting stresses on the arms. Just another issue, take a look at your backpack and case. If your arms are under stress may well cause stress?