Lexus LS460 Clicking/Knocking Sound From the Brake Actuator

Clicking and knocking at a hard stop, actuator or solonoid was first dx, now they say it is a $2300 fix!
I took it in before the warranty expired and got a clean report, now 10000 miles later this problem.
I thought these were dependable cars. My LS 430 was at 106000 WHEN i TRADED IT IN AND NEVER HAD the first problem.

Clicking / knocking sound when brakes are lightly applied. Has not been diagnosed by dealer yet.

A knocking sound is heard from the brake control module/brake actuator when applying brakes, or if the pedal is pressed while the car is stopped. I have been told there was a service bulliten issued 12-2009. Unfortunately may vehicle is out of warranty and currently attempting to get Lexus to do whats right. I have been told the cost of the new revised actuator is approximately $3000.00

Actuator replaced. Noticed the beginning of the problem at 13,000 miles and told it was normal. Now at 40,000 miles starting to hear noise again when braking. In to dealership now.

Clicking/knocking sound when breaking, Lexus diagnosis brake actuator, part ordered waiting on delivery 2 wks as of today