Considering no consoles seem to actually be breaking as a result of this, I have doubts, but I guess the sound may be pretty annoying for some regardless. And apparently some folks are reporting that they've been hearing the sound since launch or well before Kinectless versions released?
Based on when it's occurring and when it isn't happening, it certainly seems like something that a firmware update to those particular models may very well fix.
Now that I think about it, I wonder if there really are different Xbox One models, because there's a vast difference in the size of preview updates that people get from console to console. Mine are constantly in the 245MB-350MB range. Only one since I've had this, I think, has been in excess of 1GB in size, and I believe it was the very first September Preview update.
Mine is doing this exact thing. Just bought it 2 days ago. My friend and I bought our Xbox One's from the same retailer, at the same time, and his is totally quiet. Disconnecting kinect makes it even more noisy. I am not really sensitive to some noise, but this is too severe.
I'll wait a few days before returning it, maybe MS makes a statement or something. I dunno.
Folks reporting these issues should start revealing some potentially helpful info.
1. Country you're in.
2. Date your system was manufactured if it shows it
3. And possibly where it was manufactured (again if it shows it)