I had exactly the same thing with about 2K(miles) on the clock, on my first Euro trip on it.
Be aware that if you kill it with the stop switch it can be started again without the key unless you remove the battery power to it.
My barrel and keys were replaced under warranty and its been fine ever since. Now got about 14.5K(miles) on it.
It happens to RR's as well as I was on the boat back and a guy on an RR said he had had the same problem. So its a know fault !!!