Classic movie sound tracks are typically NOT in Dolby Digital unless they have been converted. That leaves thousands of great movies with either a stereo or mono mix. There is one device you can stream movies with that will upconvert any soundtrack to either Dolby Digital, DTS, Atmos or even DTS-X... the X-Box. An X-Box series S is about $300 and comes loaded with apps for nearly every major streaming service. The Shield, the Firestick, ATV4K, and Roku will play only the embedded audio track while the X-Box let's you select the audio format you like. If I am playing back a musical like Singing in the Rain or Hello Dolly and want a playback in DTS instead of stereo, done. If I am playing back LOTR or Star Wars and want to experience Atmos instead of DD 5.1, done. Once you get used to the freedom of choosing the audio codec for the selected content you quickly find all of the other playback devices seem crippled in comparison.