Why does the "trusted voice" feature not work on my Moto X Pure?

When I try to activate "from any screen" from the trusted voice feature under security settings, it tells me to say "okay Google" three times to activate. When I attempt to do this I get a prompt that tells me "can't use the microphone. Restart device."

However, I have set up the Moto Voice feature with my custom launch phrase and it works fine.

Any ideas?

I'm having the same problem.