Originally Posted by BokitoNL
But perhaps the Roku can support bitstream audio, like DD/DTS which will give you a full 5.1 audio experience for movies
The Roku can do bitstream atmos, but the HD621 can't. It can do DD+ but the HD621 can't. At best the HD621 can do DD 640kb/s, i.e. MP3 quality. Or LPCM. But the Roku wont decode to LPCM. I have heard that a 4K Apple TV can be configured to decode DD+ bitstreams to LPCM, but I have never tried it. And the HD621 can't do 4k. Very frustrating.

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