Plex Server for live tv channel

Server Version#: not sure
Player Version#: on andriod tablet samsung

Everytime i try an play a particular channel; there is an error message that reads: the server is not powerful enough to covert video

My server runs on the nvidia sheild and is doing the same thing when I try to stream outside my network. This used to work just fine before one of the last updates. I can stream movies from it just fine it only happens on the OTA Channels.