So, the HDMI CEC portion would control the devices, HDMI ARC, or eARC is for the audio return channel.
You use that to output audio from the TV to the AV receiver through the same cable that transfers the video signal from the receiver to the TV.
You might need to connect the ATV to the TV, using it to turn on the TV and then the TV would turn on the receiver, and set the TV to output audio through the HDMI ARC connection.
What is your TV model?