Hdmi_cec.standby not working

cec scan showed my TV so i added hdmi into the config as followed:

hdmi_cec:
  devices:
    TV: 0.0.0.0

reboot shows hdmi was successfully added. in http://192.168.1.233:8123/dev-service, i can see the Service hdmi_cec.standby
however, pressing the “call service” button did not turn off the TV.
am i missing something?

image

You did not select / enter the entity id for your TV.

in service data, i have to enter the TV in?
i just tried ```
{“device”: “Chromecast”}

but that did not work

That is very likely not the entity ID either. If I go to Sev States I see the entity ID of my chromecast enabled TV is media_player.kitchen_tv Yours would be different.

looking in the HA log, i see a bunch of these errors:
2019-05-08 14:30:03 WARNING (ThreadPoolExecutor-1_0) [pycec] Not initialized. Waiting for init.
2019-05-08 14:30:03 WARNING (ThreadPoolExecutor-0_0) [pycec.cec] No adapters found
2019-05-08 14:30:04 WARNING (ThreadPoolExecutor-1_0) [pycec] Not initialized. Waiting for init.

not sure if thats related to hdmi issue

FYI, I installed hassio with docker via this tutorial https://github.com/home-assistant/hassio-installer on my Odroid C2 machine.
i dont think i have to install libcec right?