I was wondering if anyone has had a problem with the headrest safety feature deploying when the car was not involved in an accident? I have a 2006 cls500 with 4000 miles. It has been in the shop 7 weeks due to deployment of headrest safety feature. The noise was sooo loud and I was struck by the headrest. Enough to cause accident because I wasn't expecting it. They cant find what happened so they are trying to blame me. Any ideas?