If you can't hear it, try using the monitor in a silent room. If you try switching the refresh rate up & down it will change pitch.
It's very distracting.
I understand that peoples' hearing abilities differ but my ears have always been sensitive so it's unusable in its current state unfortunately. It emits a high frequency "whine" which lowers in pitch the lower Hz refresh rate you select, but never goes away, even at 60Hz. My DELL monitor never has this problem.
It's not coming from the speakers- it's an electronic "buzz", also sometimes described as "coil whine" online, coming from the electronics.
I've searched for firmware updates but can't find any on acer's website & not sure if it would address this anyway.
Has anyone else experienced this problem & knows of a fix?