Surface Laptop 3 Faint Buzzing Sound

Sure, I guess that could be why.  But would having a little dock widget really affect battery life that much?  It's only using a minuscule amount of the CPU.

Did your new unit still have the buzzing?

The problem is that it isn't using CPU.  As long as the CPU is used at the machine startup and continues, you probably won't hear the buzzing sound or have dock issues.

It's when the CPU tries to enter an idle state that it happens, which is usually shortly after bootup unless you run something intensive like a game.  It's probably something with the design of the video card chipset and CPU placement, or at least what I thought when I was looking at it more.  You notice how everyone in these threads with problems have the exact same setup?  No AMD CPUs, only Intel with Iris Plus graphics...

Edit:  Sorry, I mis-read, you mentioned Dock widget and not Dock.  It's probably using enough CPU to prevent the idle state.  It honestly may not be noticeable enough to matter for most people.  I needed as much battery as I could on mine carrying it around for work, so even 15 minutes mattered.  You could try the CPU idle state disable too.  It at least won't require you to have another app loaded taking up memory and accomplish the same thing.

I also didn't get a new one, just returned it outright.  I was going to get a new one, but decided against it after I kept reading that almost everyone had the same issue with multiple exchanges.  I figure I'll find another brand or try again in 6 months if it looks like the flaw was fixed.

Sure, I guess that could be why.  But would having a little dock widget really affect battery life that much?  It's only using a minuscule amount of the CPU.

Did your new unit still have the buzzing?

Couldn’t agree more. 

Limiting CPU cannot be a solution on this product but thanks for sharing regardless!

Update: THERE IS A FIX!

If you download and install Winstep Nexus (it's a MacOS style dock for Windows), the buzzing disappears completely!  Not a single sound.   Super weird that something like this fixes it, but I guess computers work in mysterious ways. 

I don't really want the dock itself, so I just set it to auto-hide on the right edge of the screen. 

Credit goes to the guy on this Reddit thread: https://www.reddit.com/r/Surface/comments/e9xrip/surface_laptop_3_buzzing_noise/

That is probably just preventing your CPU from going totally idle.  Look on page 13 of this thread, there is a registry entry to disable CPU idle states. It removed the buzzing and fix external monitor issues for me, but I still returned my Surface because it is ridiculous to pay so much for something that doesn't work properly.  

https://answers.microsoft.com/en-us/surface/forum/surflaptop3-surfupdate/surface-laptop-3-faint-buzzing-sound/d800b696-ff7c-4cf0-a2db-99c2c2082144?messageId=74c4cd60-6492-4b04-b443-c5db53d7c1d0&page=13

It's not really a fix, just a workaround, like installing software.  Your battery will drain faster.

Hey everyone, there may be a (partial) fix to this problem.  I took the advice of one of the other commenters here and disabled the touchscreen on my SL3.  You can do this by going into the registry and setting "TouchGate" to 0 instead of 1.

After restarting the computer, the buzzing did not completely disappear, but it does seem to have diminished.  It's no longer as noticeable as before, and I feel that I can use the laptop in a quiet room now without it being annoying.  I have no interest in using the touchscreen (just switched from a Mac, lol), so this change was a no brainer for me.