FWIW, your scenario is somewhat similar to me after taking delivery of my new 2013 and believing I had a rattle with my glove compartment door. After a month trying to isolate the problem, asking my brother to double chck me as the passenger, and even taking my own solo test drive around the dealers local streets before checking in for my appointment to recreate the problem -- while I was sipping my cappuccino in the waiting area watching CNN on some massive HDTV from a comfy chair, the service technician tracked me down and asked me to take him for a test drive. After the first occurrence, he very politely suggested I remove the quarters I had put in the change holder under the center console, and the rattle was gone. Made me feel like an idiot, and I apologized multiple times, but he said it was why they were there and he was glad to help. He went on to say he knew I'd asked for my RX to not be washed, but he would be happy to take care of it. (Of course I said, "no thanks", as no one washes my rides but me.) My SA was the same way, and the whole experience was no charge. I couldn't have asked for a better way for Lexus or my dealer to have handled my complaint. It's exactly the reason I love Lexus service and will return the next time -- in or out of warranty.