Plex on Shield TV Completely Broken

Can you (or anyone else) suggest a device to act as a Plex server that has the following capabilities:

  • A direct HDMI connection to my AV receiver. (I don’t want to have stream over my home network to a separate Plex client like an Apple TV.)
  • During local playback, audio passthrough with no decoding of its own to let my AV receiver do the work
  • Smooth playback of not just 1080p MKV files, but also 4K H.265 movies as well.
  • At least 2 USB 3.0 ports to connect the Drobo 5C’s. (I have a large library and these have worked fantastically so far.)
  • Easy remote control access with a Logitech Harmony. (I don’t want to have to use a mouse and keyboard to start up and access the device.)
  • Something very small and low-power. I want to keep it in my AV cabinet and don’t want a full PC stuck in there and turned on 24/7.

(…You can probably see why the Shield TV was such an attractive option for me.)

Thanks again so much for the input!