My dealership had my car for 2.5 days. During the 2.5 days , the service mgr said they made adjustments to several "things" close to the firewall. The noise improved, but they could still hear it. Finally called and said they think they got it. When I picked the vehicle up, he wasn't there for me to speak to. My service invoice said they adjusted the heater hose mount near firewall. I haven't heard the sound since picking it up almost 2 weeks ago. Also got the TSB for break squeal done at the same time.