Hi!
Right now I am using my Mac mini to play movies on my TV and I want to know of the Xbox 360 app allows for mkv files playback without any transcoding or will my Mac mini have to work harder to push transcoded signals?
Thanks!
would like to know the same thing. my xbox360 sees my library but i get an error stating that it cant communicate to the server. im running plex on a synology ds212. i have two tvs that are not having any issues playing media from the plex library.
Just tried it on now and Plex on Xbox 360 does indeed need transcoding, so the computer CPU goes haywire.
No, it does not. Further reading: http://support.xbox.com/en-US/xbox-360/system/audio-video-playback-faq
As long as your audio and video codecs are supported though it should just remux, which isn’t terribly cpu intense. Remember that mkv, mp4, avi are containers. The codec of the video/audio stream matters as well. 
Using handbreak on most of my videos, they are .mkv. That said, it does transcode when I use my 360. I have an original released 360 which might matter over the years. Hard wired to the network.
Of course everything is 2.0 stereo so audio is transcoded. Sometimes audio is out of sync. Sometimes video pauses and freezes.
But as adamskoog said, its the stream. Some HD videos are flawless, but most have issues for me.
Server CPU is a i5 2.3ghz, usage is usually peaks at 30% every 10-15 seconds. Thats when stuttering occurs but not always so it might not be related.
I noticed that my FireTV Stick plays flawless and my cpu peaks to 60%+ when it needs to transcode so I’m thinking my 360 hardware just doesn’t have the power needed or its a heat related issue and the 360 throttles cpu/gpu. Again, maybe a condition of the 1st generation 360 also.
