i use the ipad pro 2018 to play the movie，
when i use the hdmi pass through that can’t output the lpcm 7.1 audio.
because，the hdmi 7.1 audio decoder can’t receive the lpcm 7.1 singal，
the analog 7.1 output port it’s only 2 channel(FL，FR port) can hear the sound.
then when i use picture in picture to play the movie，the hdmi 7.1 audio decoder can received the lpcm 7.1 singal，every channel’s sound is fine。
so my point is
i need to play the movie in regular mode，and output the lpcm 7.1 sound to the hdmi audio decoder ，and then i can connect to my 7.1
home theater speaker，that’s will be perfect!
so can add something to make this work？
hdmi 7.1 audio decoder like this