I'm having the same issue with getting the subtitles to come up on the Roku device, I have the latest update for mezzmo on the PC and have downloaded the app on the roku. I am having this issue whether mezzmo transcodes or not. I am also having trouble getting the roku to appear in device list on the android app, I have tried finding it while its on the roku home screen and when its in the roku mezzmo app. Is there any way to use the Roku app to connect to a mezzmo server over the internet?