Power Supply Fan is _loud_

This is a engineering issue which could have possibly been fixed via a system update. However, given the amount of time which has elapsed with with the issue lingering, I believe it is a hardware problem which will be corrected in the next hardware iteration.

The thing is, The system and even the controller have on-board chips which allow certain settings to be tweaked for smoother operation. It would seem as though the first-gen PSUs are lacking such a chip.

It would be nice to get some confirmation, but you'll never hear it direct from Microsoft. If they admitted this hardware change was in the pipelines, they'd have too many returned units. What will likely happen is the PSUs will be updated with the fix quietly.
There will be no announcement, no mention in any public change log. Just one day... Xbox One PSUs will run quietly in standby mode... hopefully.

Hello it does sound a bit like a faulty PSU. Mine is 100% quiet. I would suggest going to this page
https://myservice.xbox.com Register the console with its serial number (press menu, settings,system, console ID on that screen you will see the console ID as well as the serial number listed) And sumbit
an order for a replacement PSU. Now some folks have reported that turning the "instant on" feature off can help to quiet your PSU so you may also want to give that a try.

The power supply has a built-in cooling fan.
The fan starts automatically when you turn on your Xbox.

• The fan should make a noticeable whirring sound typical of most cooling fans.
• When your Xbox is in energy-saving mode or when it’s disconnected from its power supply, the fan is turned off.
• If your Xbox power mode is in Instant-On, the power supply and fan will remain turned on.
• The fan speed increases or decreases, along with the sound of the fan, as the power supply changes temperature.

To keep the power supply working more efficiently and safely:

• Don't block the power supply’s vents.
• Don't leave the power supply on a bed, sofa, or other soft surface.
• Make sure the power supply has good air flow. Don't put it inside a bookcase, rack, or stereo cabinet unless that space has good ventilation.
• Don't leave the power supply near heat sources such as a radiator, heat register, stove, or audio equipment.
• Don't stack electronic devices on top of the power supply.
• Position the power supply horizontally so it sits flat on its rubber pads.

Note

If noise from the power supply seems excessive, the power strip or surge protector it’s plugged into may be overloaded. Plug your Xbox power supply directly into a wall outlet instead.

support.xbox.com/.../power-supply

Power supply placement, temperature, and noise

To provide sufficient cooling, the Xbox 360 external power supply uses a built-in fan to blow air through the PSU. When you press the power button to start your Xbox 360 console, the PSU fan starts. Typically, the PSU fan makes a "whirring" noise. When your
Xbox 360 console is in standby mode or when the console is disconnected from the PSU, the fan does not operate. The speed of the fan increases or decreases when the temperature of the PSU changes. If the fan speed changes, the "whirring" noise that the fan
produces increases or decreases.

To help the power supply operate efficiently and safely, follow these precautions:

Don't block any ventilation openings on the power supply.

Don't put the power supply on a bed, a sofa, or any other soft surface that might block the ventilation openings.

Don't put the power supply in a confined space, such as a bookcase, a rack, or a stereo cabinet, unless that space is well-ventilated.

Don't put the power supply near any heat source, such as a radiator, a heat register, a stove, or an amplifier.

Don't stack other electronic devices on top of the power supply.

Make sure that the power supply is positioned horizontally and lays flat on the four rubber pads on its base.

If the power supply is making excessive noise, you might have a power strip or surge protector that is overloaded. Plug your power supply directly in to a wall outlet and see if the problem persists.

the slim power supply has a fan.