I just purchased an 08 TL and this is the first issue that I've come across. I saw threads from over a decade ago that addressed the issue.
This user explains it perfectly:

Some say that it develops over time. I feel that way because I never noticed it until this week. I bought the car 2 months ago. Some people even took it to the dealer and the dealer claims that it's normal.
Some say that it's the nose from the shift solenoid after the grease wears down. Others say that it's a plastic part that's bumping against something. It's not a major problem but it is annoying. I'm not skilled enough to take the console apart and really don't want to take it to the dealer. Is there any remedy for this that won't involve me going into my pocket?

 

if you dont want take stuff apart and you dont want to take it to a dealer/mechanic, the only way to not spend money is to ignore it.

 

You certainly are skilled enough to take care of it! Youtube has lots of videos on how to disassemble and fix issues. I'm thinking your safety switch needs grease or to be replaced.