Just got my Mi Box tonight and its mostly working as expected... except for surround sound output. My receiver doesn't support HDMI audio (only video... its old) so I've been using optical. No matter what I have set in the sound settings, I only get stereo output. Is there some trick I'm missing?
I was having a similar problem with my mi box, my receiver does support HDMI audio but was unsure if it already had surround sound setup. I was able to tell when a movie had 5.1 next to the HD on Netflix but non of them had it. So I switch it to the built in crappy Netflix app and it did show 5.1 even the super HD. So what I did found a movie that had 5.1 in the crappy Netflix app and play it on the mi box and I was able to tell it was playing surround sound. Not sure if the app needs a update to let me know if it supports surround sound. I tried the movie Zootopia which has surround sound and I was able to tell on my sound system. Hopefully they helps because I notice a bunch of movies don't have the surround sound and with the crappy Netflix app I was able to tell which one do, but not in the mi box.
I am also on a non hdmi reciever but this thing has solved all problems https://www.amazon.com/J-Tech-Digital-Extractor-Outputs-Setting/dp/B01296E5OO/ref=sr_1_1?s=electronics&ie=UTF8&qid=1450713147&sr=1-1&keywords=hdmi+switch+toslink
Xiaomi suggested trying a replacement unit, which I guess I will be doing later today. I'm sure its the standard line from support, but they said they will be looking into adding an option to forcibly select which codecs/channels will be output in a future update.
I am having the same damn problem. Im in Canada and was a pain to get this thing. I also am using an older non-HDMI receiver so i purchased a SPDIF/toslink:
https://www.amazon.ca/gp/product/B00016W6Y6/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
But I am only getting Stereo sound instead of DTS/DD(AC3) when testing files with Kodi and VLC. I literally purchased this box because of its optical audio out.
Had the same issue, updated the software and that fixed it
Kodi and VLC do 5.1 passthrough over s/pdif for me. But not Plex or Netflix. You need to go into the advanced setting of kodi as usual to enable it.
This is my setup: MiBox>HDMI>TV>HDMI(ARC)>HomeTheater
5.1 Dolby surround test file works via VLC Not worked on Netflix
I guess the problem is with the netflix app.
Did you go into the android audio settings and tell it to use optical audio and not "auto" or "HDMI"?