Apple TV no surround Sound

[Malko]

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I have been using Jellyfin for sometime, and I finally got surround sound setup on my apple TV.
So if I play John Wick Chapter for.  its a 4k 5.1 or 7.1 file.  I get no sound out of the rear speakers in my system.  If I play that same file on my Iphone and air play it to the apple TV I get surround sound.
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I am running Swiftfin (1.0.1) on an 4K AppleTV (A1842) running tvOS 17.3. When viewing streaming media from a friend's remote server, I could not decode surround sound (either 5.1 or 7.1). I eventually solved the issue by selecting Settings > Experimental > Use fmp4 with HLS > ON in Swiftfin. I did notice some lip sync delay which I addressed by recalibrating wireless audio on the AppleTV using my iPhone as a microphone (AppleTV > Settings > Video and Audio > Calibration and then follow on-screen instructions.)

Of note, turning on Force Direct Play in Swiftfin's Experimental section resulted in picture but no sound. Turning on Native Player resulted in surround sound with no picture. 

I hope this helps other tvOS Swiftfin users with the same issue.