Asus LCD monitor - Service Center problem

[Beka Kalandadze]

Hello friends.
So, here's a little customer story:
I bought ASUS LCD display 2 years ago (on 03.12.2016) and got a warranty for 3 years of repair service.
About 3-4 months ago display started to make high pitch noise on contrasted pixels (Like in Excel or This photo).
The noise is like that:

1. Only Sound
2. Video
3. Youtube Video

Reading the forums and having some personal knowledge I found out that it may be a capacitor or coil whine.
But the problem is when I took it to the service center officially certified by ASUS, after diagnostics I got an answer that, "It is totally normal for the displays to have that kind of noise". So called "Expert", even scratched my screen, which I did not see until I got home with a display. Main idea behind "making no repair" was that Decibels are in normal range of what it should be.
Well, I am pretty sure most of you will agree that it is not and I want to ask if you have some kind of ways or knowledge what should I do.
ASUS is telling me that my only option is to "Write a complaint to the Service Center", which is no real option, result will still be the same, nor the re-seller, nor ASUS want to back me up.

I would like to add that even ASUS doesn't want to write me about the question "whether or not is this sound normal behavior for a display monitor?"
Anyways, Please guide me in that situation.

Thanks for your help.