The microphone on your Kinect sensor needs to be calibrated so that it can hear you above the ambient background noise in your play space. The sensor does most of the work, making this an easy process.
How to calibrate the microphone
Turn up the volume on your TV's speakers, so that it's above the level you normally use to watch films and shows. At the same time, make sure that your room is quiet.
Start the calibration process. Here's how:
Scroll left on the Home screen to open the guide.
Select All settings.
Select Kinect & devices.
Under Troubleshooting, select Kinect doesn't hear me.
Select Start audio check.
The calibration performs two tests:
Check background noise: Kinect monitors the ambient noise level in your play space. If the level is too high, the sensor displays a message asking you to check for noises in the room and then to restart the calibration after you've muted any background noise.
Check speaker volume: Xbox One plays a series of tones for Kinect to hear to calibrate the audio playback level. If the audio tones are too low, a message asks you to turn up the volume of the speakers. If the sound levels are loud enough, you'll see a message telling you the audio check was successful.
If the tests are successful, the Kinect sensor's microphone self-calibrates. This is automatic, so you don't have to do anything during this step. It should take only a few seconds for the self-calibration to complete.
When the calibration is complete, the Kinect sensor will be ready to hear you.
Note After three failed attempts to perform audio calibration, you can either press the B button to retry the calibration, or you can come back to try this again later. When you're ready to try again, repeat the procedure above, starting at step 2.