It's the wastegate actuator. It's normal on all turbo cars. When under load, there it tension on the arm and no noise. When off the throttle, there is no tension on the arm and it vibrates and makes the noise you are talking about. If you pop the hood, you can wiggle the arm. That's what you are...
I'm in Cleveland and would be interested in taking your spot but I'd need Crown to agree to what I'm looking for but it doesn't sound like they would be willing to agree to it. I'd be looking for their next silver, blue, red or tiger eye (all with the black interior) at MSRP. Refundable deposit...