For those of us in Canada, it is not possible to have the Xbox One power up a cable/satellite box unless you use the following workaround:
– Under Settings, change your location to United States instead of Canada, reboot your XBox
– Under the OneGuide settings, under Devices, you should now see an option to configure your cable box. Follow the wizard to do so
– Switch back your location to Canada and reboot again
You won’t have the OneGuide but the AVR, cable box and TV will power on/off with the voice commands.