Double or nothing on 3.0?
LOL Sure.
As someone who has made a living in technology for some 40 years, this has been so frustrating. Not only is Plexās multi channel music support not working, Embyās use of the ATV music player is broken and my ATV will not see any DLNAās on my network. My Roku doesnāt seem to like multi channel and my Chromecast is just too painful to use for this. I am now bypassing the ATV all together and am using the DLNA player on my receiver (along with its iPhone app). There is no gapless audio, but at least I can play multi channel FLACs. I feel like Iām in the 1980ās again where nothing would work as advertised.
So, how we doing? Itās closing in on 6 months since my first post. Any ETA at all?
crickets
Version 2.10 is now available⦠but about bug 5.1 : NOTHING !!!
Yep. I tested 2.10 last night and was mildly disappointed. @mikeshare56, they arenāt up to 3.0 yet, so the bet is still on. 
Meanwhile, I couldnāt wait. I have friends coming over in a month and there is no reason to believe Plex will be ready. So, my semi-permanent fix is to use JRiver. I used the word permanent because I had to spend money to get there, so Iām going to live with it for a while, no matter what Plex does. The process was a bit more complicated but the results are pretty good. I have JRiver on my Plex computer, but it is in another room in the house, so I purchased an HDMI over Ethernet kit. That meant I had to redo how I wired, which meant that I had to change out my router for a mesh router (giving you all the short story here). So, now, I use an app on my iPhone to access the music on the JRiver/Plex server and it plays very nicely on my receiver. Not only that, but they have this thing called gapless audio (insert sarcasm here) and it is soooo good, if you close your eyes during Dark Side of the Moon and listen closely, you can not hear the songs switch. On the negative side, I have to use my ATV remote to control volume (or I can switch apps to my Harmony app to do it as well), and, it isnāt part of the Plex system. Otherwise, itās an excellent solution right now⦠and it sounds really good.
Hope thereās a better alternative! I canāt believe we canāt get a better response from the fine folks who are providing this forum!
Same problem on Android TV, and for months now as well. Are you guys able to play 96k or 192k FLAC in stereo at least?
Well, Iād love to have it all in one app. But actually, I can get to an album using the JRiver remote software faster than using Plex on my ATV. Of course, Iām the only one who sees the browse of the files. Not sure if that is a good or bad thing. They also have nice touches like quick fades in and out when you start and stop music. It isnāt as jarring. Maybe its for the best since we obviously arenāt important enough of a sub culture for Plex to make us a priority. At least at JRiver, it starts with the music and then there is there other media. Itās nice to be part of the majority for once.
Stereo? Whatās that?
Sorry. The only things I put up on Plex are multi channel. I can tell you I believe it is playing my multi channel in 96k, but only 2 of the channels.
I made an interim solution and concatenated all my 5.1 m4a-files into ac3 mp4-files per album, with cover and chapters, put them into a āother videosā mediathek. This plays fine. Have done a little php-converter you could run via MAMP on Macs, so if you are interested send me a PM.
Thanks for the offer. Iāve seen a version of this hack for iTunes as well. My issue is that I already have 2 versions (FLAC and ALAC) for a half terabyte worth (for each version) of music and I canāt delete either of them because I donāt know which direction Plex is going. Originally, it required ALAC on the ATV. When I was testing Emby as an alternative, FLAC was the way to go (and my preference). A third copy would just be crazy talk.
Iām really liking the JRiver alternative, these days. I may not go back to Plex for music. The reason for Plex is so that my wife can easily play things without my help. But she is not at all interested in the multi channel music, so it really doesnāt need to be in Plex. And now that I have a nice JRiver setup, Plex will have to do a really good job on this update⦠whenever it comes out.
Iāve got an interesting bet for any takers: Which will happen first, the multi channel music fix or Tidal going under. 
And you know, Iām not the kind that sits around attacking a company on its own site, but 6 months is a long time for a whole section of the program to not work. So, any empathy I have towards them right now is pretty low.
So⦠2.10.1 is out. No change. Itās funny how even the IOS app is not working properly (it doesnāt down mix the 6 channels) but if I run Foobar on my phone and use the Plex DLNA, it properly down mixes.
Came here to complain about this issue. Glad to see itās not me but the OP is from may and this still isnāt fixed???
Yep. I think they want us to buy into Tidal instead.
Does tidal offer 5.1 music?
Nope.I was just being sarcastic.
I have been software developer from the beginning for the last 40 years.
Iām wondering what people are doing these jobs today, that such an issue takes ages to get fixed!
Iām guessing that there are just more problems then there are programmers. Our area just isnāt high enough on the priority list.