I know there are others with Cayman's who have been plagued with noises from behind them in the car. I just wanted to share what I have found. I gutted the interior of the car from behind the seats to the rear and drove with it for several months this way to find them.

1. The taillights vibrated so I cushioned them on the tops and bottoms with felt tape as well as on the light bulb rail to firm it up and this corrected the problem. I would like a better solution though.
2. On the rear of the headliner there are 2 Velcro fasteners that are very loosely snapped into the roof that rattle. These are completely unnecessary and I have removed them.
3. The wiring harness on the underside of the hatch lid I removed and put felt between it and the fasteners as per a recommendation from another thread.
4. On the intake side there is a wire-rail under the cargohold/behind the drivers seat belt. This taps the sheet metal. Felt tape corrected this.
5. The rear speaker covers vibrate. I cut them off and will re-fasten them more appropriately later.
6. Where the strut tower covering joins with the cargohold trim piece I used felt tape to stop the plastic ticky sounds.
7. The metal framwork that surrounds the rear latch mechanism vibrated. I tightened it up.
8. There was a plastic cap that fell behind some sheet metal behind the trim. That was removed.

Last and the BIGGEST problem I am still having that took me the longest to find because I just could not believe it I think - There is a spot weld joint that is behind the courtesy light in the rear between the rear window and strut tower that ticks/cracks. I confirmed this on a particular road with someone pressing on the joint. This can be heard through all of the plastic trim and drives me insane. I do not know how to correct this and seriously doubt any dealer or Porsche will help, even though this has been happening since day 1 of this new car as the dealer has already said " Sorry, 3000 mile rattle warranty, thank you, drive through please." I will fix this myself but could use some advice on how to best do this.

Porsche, I hope you are reading this. After this experience so far I seriously doubt I will ever own another. This is completely unacceptable for a 70k car.