Please understand that you took your computer to an Apple Genius employee at an Apple Store. This Apple Genius was able to see, touch, feel, smell, hear, etc. the computer...and they gave you what they thought the source of the clicking was.
Now you've posted on an internet forum a question about this clicking...which we would be more than happy to try & help solve.
But you must understand...we are at a distinct disadvantage compared to the Apple Genius that examined it. We cannot see, touch, feel , smell, hear, etc the computer.
So you are really, really, really, really going to give us a lot more information than what you've given us so far!!!
- We have no idea what this clicking sounds like.
- We have no idea what general area it is coming from.
- We have no idea what causes it (if a certain action causing it).
- We have no idea what model retina MacBook Pro it is (could be a 13" or a 15"). It could make a difference.
- We don't know if the clicking is something caused by software or hardware.
Remember...this is the internet. We cannot see or hear what this computer is doing. So you NEED to describe things in GREAT detail so we can help!!!