Question: onkyo how to use arc?
Answer: Press Setup on the Onkyo Remote.
Assuming you have OSD enabled, you will see the setup menu on screen.
Go to Hardware Setup.
Go to HDMI.
Set HDMI Control (RIHD) to On.
Set Power Control to On.
Set TV Control to On.
Exit Setup by pressing the Setup button on the Onkyo remote.