We have owned our 2012 SLK 350 for about 3 months. The car has a very annoying intermittent problem of not starting. Each time this has happened, the car had been driven, shut off for anywhere from 10 minutes to an hour or so. The key is inserted and turned and there is no response. The steering column goes down as normal but the instrument panel does not light up and the radio does not work. There is no starter engagement. If you sit there for a while and keep re-trying, the car starts. There is no rhyme or reason as to when this may happen. Has anybody experienced this?