I hear some noise when start the engine in the morning.

I have attached MP3, the noise at 5 to 6 sec.

2007 IS250. changed water cooler and drive belt recently.

 

I had my volume maxed out and still couldn't hear it very well. I immediately thought "cam rattle" when I first read the thread; however, the "odd" noise happened after the initial start-up, so I'm not quite sure since I couldn't hear it too well.