My H96Pro+ box can only output stereo sound and no 5.1 over HDMI. (with settings: Surround Sound Always and Output: HDMI)
KODI shows stereo downmixed even if I choose 5.1.
Plex only outputs the Left and Right channel (Plex doesn't do downmixing on the player side).
However I can force stereo downmixing over HDMI with the following sequence (tested with Plex but have to redo after restarts):
starting system with Surround Sound: Always + Digital sounds: SPDIF
Surround Sound: Never
Digital sounds: PCM
Surround Sound: Always
Digital sounds: HDMI
Digital sounds: SPDIF
Is there a way to enable 5.1 HDMI ? or enable stereo downmix on HDMI after system boot?