Force AAC 5.1 to AC3 5.1

[closesim]

Hi. I'm not sure if this a bug or misconfiguration. Assume a video container with HEVC and AAC 5.1 normally gets direct play without ttanscoding in a Roku Ultra LT. In this scenario the Roku appears to handle the audio stream and mixes it to stereo automatically even though the Receiver supports 5.1 PCM. I was expecting that Jellyfin could remix the audio to AC3 or EAC3 to allow bitstreaming to a Receiver without losing the dynamic range and bandwidth of the 5.1 stream.

Describe the solution you'd like

An option to force transcoding AAC multichannel to Dolby based multichannel format that can be supported with devices with eARC, ARC or directly connected to a Dolby supported Receiver, with the original video stream.

Describe alternatives you've considered

The Roku mixes all multichannel AAC to Stereo in all scenarios.

Additional context

My setup consist in a Roku Ultra LT connected to a Jellyfin Docker container over wifi. The Roku is also connected to a Onkyo Receiver over HDMI.

Related issue:
#117 (comment)

[cewert]

I took a stab at this once. I plan on giving it another shot but don't know when that will be #1466