What is this engine whining noise?

I just replaced my alternator and my idler pulley.

[stoichiometry]

FYI: I passively chased the same whine (which sounds like a power steering low on fluid whine) for 4 years. I have a 2012 BK1 Genesis Coupe 2.0 w/ 35k miles.
I replaced the P/S pump, Alternator all the idler pulleys, one at time.
It was on the accessory belt, because when you remove belt tension while idle it gets dead silent.
Long story short, it’s a bad bearing on the air conditioning compressor pulley. I was also told by a Hyundai tech, it was semi-common on pre-2013 Hyundais. Especially since mine has had 1-2 year periods of sitting and not running a few times. The bearings races are made of cheap metal and the roller or balls inside leave an impression from the belt tension while sitting for a long time. The pulley is $100 from oem online or $325 for the oem compressor assembly. Pulley is easily replaced but not while mounted to the engine. Discharge and replace the entire unit. .
P.S. don’t buy a used replacement, it’ll have the same crappy bearings.
Hope this helps someone

[AbualHassanPervaizAkther]

i have same noise even AC is not switched on yet. it goes away after driving few minutes. comes back when engine is cold.

[taylorshea]

It’s one of your belt pulleys or bearings on them are bad I saw someone else had the same issues

[adaltre]

I had a similar problem turned to be the ac comppresor was going bad

[bollmandarren]

I have this but I also have a burning plastic/ electrical smell.... Also started to smoke white pretty bad too.... I'm assuming that's not going to be an accident compressor?

[patemathic]

I'm guessing it's the turbo?

[LioncuhbzCODM]

No way my car does this exact same sound, would it be bad to keep running the car with this noise problem?

[garycarreon]

hi sir, what is the problem after diagnose this whining sound?let me know?

[Zar]

same with my BK1 issue pag nag start ako

[.ahmed]

did u figure it out? i have same problem

[Onlymeee]

I have the same 😢sound did you figure out what it is ?