Question Audio Jack High Pitch Noise with LG Monitors

Apr 1, 2021
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I'm in the UK and the 34GN850 had just restocked last weekend and I purchased it after months of waiting.

The monitor came with a faulty headphone jack which gives this very high pitch noise whenever there is audio playing. I was surprised because I have encountered this issue before for my last monitor which is the 27GL850, which I had to return and bought a 27GN850 instead which didn't have the problem.

I returned the first 34GN850 and purchased another unit which still has the same issue. (surprisingly none of the two units suffer from dead pixels or blb which I heard is a typical LG issue)

Here are the problems on two separate monitors:
LG 34GN850 Audio Jack Whining - YouTube
LG 34GN850 Audio Jack High Pitch Whine - YouTube

I'm not sure if everyone will be able to hear the problem as people's ears have different sensitivity to high pitch sound, but all my friends and my roommate said that it's very noticeable.

It's definitely not the problem with my speakers since the problem is only present when connecting it to this specific monitor. I have also tested other headphones and speakers plugged into the monitor's headphone jack and they all have the same high pitch noise.

I initially thought the problem is related to ground loop and I unplugged everything and even bought a ground loop isolator which didn't fix the problem at all.
So far I haven't found anyone on the internet with the same issue. Have you guys seen anything like this?
 
Apr 1, 2021
5
1
15
0
BTW I have found a way to replicate this issue.
https://szynalski.com/tone#14000,v0.23

I've tried to find a rough frequency this issue causes which was found to be around 14,000 Hz.

Basically whenever there is audio playing through the headphone jack a sound like this comes out.

Maybe this will clarify the issue.
 

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