The Windows 10 Anniversary Update on the Xbox One, which was released on the Xbox One under the name Summer Update just a couple of days before the desktop update rolled out, adds Cortana as your default voice control option on the console.
I have been on the Xbox One Preview Program for this entire update cycle and although she was initially very skittish and had her share of issues, she has settled in pretty well on the console and works quite consistently for me.
However, that has not been the case for everyone. Her responses can be slow compared to using the old style Xbox voice commands. The main reason for this delay in responding to your voice is that Cortana processes that instruction through the cloud unlike the Xbox voice commands which are handled locally on the console.
During the preview program Microsoft did not give users any other choice but to use Cortana on the console in order to fully test the feature but after feedback from users they did implement an option to turn her off on the console.
Here is how you disable Cortana on the Xbox One console.
Step One: Open Xbox Settings>System
Once you are on this page just look for the Cortana settings option. Highlight that with your controller and then press the A button to open Cortana’s settings.
Step Two: Disable Cortana
After opening the Cortana settings look for the On/Off toggle near the top and select that with your controller and press the A button.
Read the warning about turning off Cortana for your console and the limitations that it will introduce and if you want to shut her down then just highlight the Restart now button and press the A button to restart your console.