AppleTV crashes when Airplaying Prime Video from iPhone 6s

I'm pretty sure I could do this prior to iOS11 but today whenever I try and AirPlay a playing Prime video stream, the TV goes dark with an error about "No channel available" and about 3 seconds later the video restarts playing on the phone. Is this a digital rights issues, or simply the AppleTV crashing? I need to hold down the screen button and then restart the AppleTV to get it back.