Remember when I bought a Xone and reported a lot of noise when my Xone is idle? someone made a post about the reason:
XBOX ONE COIL WHINE ISSUE <SOLVED>
Okay. Let me start off that I am updating my original post to provide the results of testing this issue (and also to overlap the incoherent banter that rests below this post). The results are in: kinectless XB1's do indeed have the aforementioned and suspected Coil Whine.
Quickly, the sound we are hearing is the sound of disparate electrons; its basically electric waste. Harmless? Most likely (ultimately based on the integrity of the capacitor cap sheathings- and I don't know of their quality), but certainly annoying. We have some components to consider here, or, specifically the coils built into these respective components' capacitors (electrons pass through these). The components in question: The motherboard, CPU, and GPU. The powerbrick (PSU) plays a role because it provides the power rail (wattage) that the duty cycles of the components are created from. It is a problem of these duty cycles that there is basically a much higher load of power (faster duty cycle) affecting these capacitor coils' native threshold, which in turn creates a resonant frequency that is likely picked up as interference by the motherboard's integrated sound card. Lessen the power load (slow down the power cycles), the sound goes away or grows fainter. The duty cycles of the aforementioned components are in complete disarray when compared to XB1 with Kinnect*. The sound is reminiscent of an old school HDD in read/access mode- but no worries, it is not your HDD. It is "power ripple." Electrons. The XB1 is affected into a "steroid mode" with the help of a script in this latest update (remember software "talks" to hardware) and apart from being annoying- our electric bill's will probably not be as slim as they could be, though nothing to significant, I hope.
The problem, I have gathered, likely goes back to the tampering of the OS in the form of an update to give the XB1 the extra 10% GPU power increase that allowed for Destiny to finally be developed with 1080P resolution. There is also some hinting that the family of GPU's that the XB1 GPU chipset belongs to is susceptible to coil whine. The only solution to this problem is as follows:
1: Microsoft can provide us all with new PSU's to accomodate the power scheme of the kinectless XB1.
2: MS can provide a script in the October update to help balance the power management (OS) within the kinectless XB1.
3: Microsoft can provide us new kinectless XB1 users, with free kinects.*
4: Microsoft should increase the quality of the capacitor cap sheathings and install a sound buffer in the components affected in newly produced XB1's.
*Now, for the part you've all been waiting for. I am pleased to confirm that the idea of adding a kinect to a powered off XB1 then turning on- largely mitigates the noise. The noise appears to still be present- BUT- the resulting power draw creates a much slower, fainter, and acceptable level of sound. It becomes largely unnoticeable- and that is only when your box is idle. Open a low level app- the sound is gone (before was the opposite). I would go as far as to say the level at which the sound becomes is within likely normal parameters for the given architecture. It also becomes sporadic, disappearing altogether (if you can hear it) at times. Seriously, the only way I could hear anything with the kinect plugged in was if I got up and walked the 8ft to my box and put my ear to it.
Needless to say, I am getting a kinect. I do not recommend returning your new machine for a refurbished one. The residual noise that may appear after kinect is plugged in will likely be addressed in a future update. I highly doubt that it will be there for the life of the system. The good news is, is that even if it were, it is not noticeable, it is harmless, and it eventually disappears; only returning sporadically. The reason for this is I suspect goes back to the update that allows XB1 to get the 10% GPU increase. Remember, NOW in that update the kinect has the abiity to return its power draw back to the GPU if needed for a high demanding instance of a game that requires more resources. It is likely that most XB1 users do not take heed to the sound when power goes away from the kinect because they likely cannot hear it and they prone to be unaware of it being an issue because they have always had kinect plugged in.
I would not steer anyone wrong. Get the Kinect- you won't regret it. Not only will it reduce and virtually mitigate the coil whine, but from just testing it out- its a pretty damn cool feature to issue those voice commands.
Currently Online 
(not that I think it'll be scary, just not my type of game) I mean who wants to play as some defenseless dude who can only run away? Sounds boring. That's just me though. Would be nice to get a full retail game though. 
