If you’ve had problems with Apple TV Airplay mirroring from Mac to your TV such as jerky or stuttering videos or problems streaming Netflix on your Mac, you might find it easier to use Plex anyway. Plex can also be used to connect your Mac to any streaming device including Apple TV, Amazon Fire TV and Chromecast so it’s definitely worth installing if you use more than just Apple TV. Plex works with virtually any version of Roku including Roku Express, Roku Premiere, Roku Ultra, and Roku 2, 3 & 4.
Plex is a free open source content delivery platform that allows you to watch, manage and stream multimedia content from your Mac. On your Roku device, first go to your Roku channel store and download Plex for Roku.