Media Players showing up as lights in Emulated Hue

I’m pretty new to Home Assistant, but in the two weeks I have been able to do some nice things for my home theater. Following great examples from the community, and being patient with learning YAML’s requirements has paid off. However, I’m having an issue that I hope someone can provide direct assistance.

I have the emulated hue setup, and my harmony hub sees my tplink lights. Which is great because I have been wanting to map them to a physical button on my harmony smart control remotes for awhile. That is working fine, I can hit a button on the remote and the appropriate light turns on/off.

The problem is that the emulated hue is exposing everything in home assistant as a “light.” Media players, switches, and amazon echo’s all appear as lights to the harmony hub and the Amazon Alexa app. I can’t figure out how to prevent this behavior.

I have tried hiding media players, via the hidden: parameter, but I can’t get it to work. A full restart of HA, and a refresh of the hue in the harmony app still shows the offending media player. Here is what I have tried in the configuration.yaml file.

emulated_hue:
  expose_by_default: true
  exposed_domains:
    - light
  entities:
    media_player.55_tcl_roku_tv:
      hidden: true

Can someone give me a pointer on how to exclude the media players and amazon echo’s from the emulated hue in HA?

Thanks in advance for helping a newbie out!