So after I start the engine lately it developed a clicking/ticking sound with a delay of a few seconds after the engine started. Diagnostics don't show anything
Ticking starts at 5-6 seconds into the video (notice the engine changes the sound too)

https://www.youtube.com/watch?v=CvzGK3rNSYg

It's an F30 320D with 150k km and it just started doing this few weeks ago. Any idea what could it be?