Hi!
I’m aware of the sound you are referring to. It is coil whine of a certain component on the motherboard. Luckily, it is nothing to worry about, but I can imagine if you find this disturbing.
It is a very low volume sound which shouldn’t be disturbing for most users, but it can still be irritating for users that work a lot in very silent environments.
I found a workaround to massively decrease the volume of this ringing sound, as the sound is coming from a specific area. I was first thinking of sound reductive foam, but I’m afraid it can burn too easily. Therefore, I choose heat pads instead. And they seem to reduce the noise quite well. Please have a look at this attached image:
NovaCustom customers can apply for these heat pads for free if they contact support directly.