ReadyNAS 214 "Server not powerful enough" streaming HD 1080p

I guess I should have provided a few more bits of info. YES, I am using Plex on both servers. YES, they are both ARM processing. While I'm away I stream my movies to my S8 Note or whichever phone I have at the time. Lower quality playback such as 480p is just fine. At home, and this is the main reason I wanted something to play HD, I have a TOL Sony. So, in my mind, I wanted to be able to stream locally all my HD movies to that TV which is hardwired to the network. I own over 1800 titles, so looking for a disc isn't always something I want to do. I can also copy 4K movies, but don't think the server will do that either. As for audio, I was hoping to get the most out of it. I have an 9.2.2 system, so the audio from the recorded movie should contain the full HD audio, else, I might as well use the disc. I'm probably wishing for something that will require a $10K transcoder in a cheaper unit such as this Netgear. I haven't looked into Direct Play. What is it exactly, and how do I use it.

Thanks for all your feedback