Guys! I need your help.

I have a 2007 infiniti m35x

For the past couple of weeks I have been getting this strange noise coming from the engine. Seems like it's coming from the front. This noise is hard to replicate because it only occurs after driving for like 2 to 5 mins or longer sometimes. Somedays I could drive and the noise is not there at all. If I shut off the engine and start it again it disappears and returns only after driving the car again. Initially I thought it could be a bearing in one of the pulley

What have I done so far?

1. I have taken the car to about three mechanics because they cant replicate the issue.

2. One mechanic checked the belts and pulley. He noticed some play in the ac compressor pulley. He took off the AC compressor belt and I drove without it but the sound came back the next day (which is today). He did this to try an isolate the noise and see where it could be coming from.

3 the noise comes on with or without the ac on. Which made me believe it may not be the ac compressor

4. One strange thing I notice is that if I switch from D to N and reverse the noise disappears.

5. I dont believe this is a power steering issue because if i turn the steering wheel. The sound is still there at a consistent volume. I have had powering steering issue before and it doesnt sound like this. I already changed the whole powering steering rack like two years ago. And the fluid level is normal. I could also be wrong about this completely.

I am just clueless and need opinions or advise in case someone has experienced this before.

Please see video below for the noise.

Hmm...that definitely sounds like something in the belt/pulley area but I'm surprised the mechanics can't replicate it. Does it seem to happen more/less with temperature changes?

Many thanks for responding. It is kind of confusing to be honest. From what I have noticed so far It happens regardless of temperature but it seems to happen less when it is cold. It is hard to replicate, that is the problem. Today for example I drove for about 10 minutes and the noise was not there. I drive the same distance /path every day and I hear it some days and some days It is never there. One thing I am certain of is that the noise only comes after driving and once I shut the engine off and restart it it is gone till I drive again.

Maybe it's not so much temperature but moisture related...? Where are you located?

I am in Ontario, Canada. Yesterday the noise came back and it Seems to be a little louder. I took a closer recording of the engine. I still cant figure it out. So far I have the ac compressor belt off because the mechanic said he heard some play in the pulley. But the noise is still there.

https://youtu.be/3QLVOQBdpgI