I had this happen but don't remember which car it was. It was either a b44 or a RC8. It would only happen on one side but not the other. After taking both sides apart, I noticed there was two sets of pin holes where the bone meets the CVD. The side that kept popping out was on the inner side, making the overall length shorter. The other side was on the outside hole making the CVD longer. I removed the pin on the one that kept popping out an put it in the other pin hole to make it longer. Never had a problem again.

I tried looking it up in the manual, but the manual doesn't talk about two sets of holes. This may or may not be the problem, but I thought it is worth a shot. If there are two sets of holes then it is definitely the problem.

Good luck.