Activating "Hey Cortana" with Bluetooth headset or speaker

[lrn2board]

Is there a way that I can initiate hey Cortana by the microphone on my headset or speakers? I feel like that would be a great feature of I'm charging my phone and using a speaker to hear the weather or to play music

 

[MoshMast]

My Bluetooth headphones have a voice command button which just to happens to trigger Cortana. It's supposed to be for Siri/Google Now, but I guess the BT profile just sends a universal signal to the phone. See if yours has a command for that!