This is normal behavior. The 200's brake booster is intrusively loud - more so on my Cruiser than LXs naturally.I have a 2018 with 13k miles on it. I can hear the brake booster loud whining coming through the firewall, just pressing the brakes, without the car being in motion... Any 2018 owner that does NOT have the issue? If that is the case, it proves that there is a problem with some boosters and Toyota should stand behind it!