HDMI Control and ARC do not work if the TV is connected to the Monitor2 output. Connect the TV to the Monitor1 output. Then, on your TV, bring up your Smart Home menu. Go to your sources. It may show HDMI 3 or Denon. Move over that selection and an arrow will appear above it. Press up, the top of the circle on the remote control, and it will bring up some options. The top selection will be Anynet+(HDMI-CEC). Click on it and then click on refresh devices so the TV can figure out which devices are connected and using HDMI Control. Have you ever run the Universal Remote control function on your TV. It works in conjunction with Anynet+. When it works properly, it's a thing of beauty and all you need for basic watching and switching of devices is the TV remote control. Though, I think you said you have a Harmony remote control.