Even with my volume turned up, I can barely hear the sound in your clip. It might be coil whine. Essentially, coil whine is the audible effect of components vibrating when under high load / high power. It can sound like a whine or a rattle or a vibration. This happens with many components, but often it's not loud enough for us to hear or at a frequency that we don't hear well. These two pages have more explanation and some tips to reduce the effect: Unfortunately, you may not be able to eliminate it to your satisfaction. Much depends upon how you use your computer, the acoustic qualities of your room, other ambient noise, etc. I once had a Netgear router whose coil whine was particularly annoying to me. I found that the volume varied among units of the identical model. I tried two or three other units of the same model in the store, and found one that I couldn't hear. Even though they were the same model, same components and power supply, two or three of them were loudly annoying to me, but the last one was inaudible.
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m15 R6, weird noise under keyboard area