I have a 2018 Camry (less than 5K miles), and when it's in gear with my foot on the brake, it has a loud idle. The first time I heard it I was in line at a McD's and I thought to myself, "I hope that it's that guy's car. That sounds bad." I just assumed it was his, seeing I had 4K miles on my car. I was in my driveway, and my husband came out and asked if it were my car making the loud noise. Sure enough - it was the same idle noise that I heard in the drive thru. It's a loud clicking sound when in drive or reverse with the a/c on.
The Toyota dealer is saying it's nothing - just normal noise. However, the fact that both of us thought it sounded off on separate occasions is giving me red flags. Especially because our 2017 RAV and my old Yaris didn't make this noise.