Brand New Audi A 6 stalls for no reason.

Seven days ago, I picked up a brand new 2008 Audi A6, 3.2 Ltr.

I drove it about 400 mostly highway miles to Cape Cod and it now has 545 miles on the odometer.

This morning I was taking a left turn at slow speed, well under 20 mph and the car just stalled. I coasted to the curb. Pushing the start button did nothing. I opened the car door to shut the radio off. Pushed the button again and it ran.

Took it to the dealer. The ran their computer diagnositics and scan. Saw nothing. Never had this problem before. They don't know what to do. I don't either. I left it there.

Should I drive it again and see if it happens. Or is that too risky a proposition and should I ask the dealer for a new car?

Thank you.