Greetings from Roku Community.
All the movies and TV shows accessible through your Roku streaming player are available in stereo; however, some are also available in surround sound. Although most Roku streaming players do not decode surround sound formats such as Dolby Digital Plus or DTS, they can pass through the signal to an audio/video receiver (AVR), soundbar, or TV, that is capable of decoding surround sound.
To learn more, visit our support page: How to set up your Roku streaming player for surround sound
We hope this helps. Please let us know if there is anything else we can assist you with.