SO I have been using channels on my Apple TV to try and stop using TiVo. I thought I finally found some thing that could work as well as a tivo.
However all I can get is a stereo output. I know the Apple TV can do it am I missing some setting on Channels to enable it. Or is it just not possible. I am using the homerun OTA 4 channel tuner. It does the same with stereo output But watch the same show on tivo in dolby.
Really seems to be a great app if I can just get all they toys working
In the Channels app under Settings > Support > Test Surround does it play back on your speakers correctly?
How/where are you seeing stereo vs dolby.
The input to my Sonos Arc shows it. When watching Channels it shows PCM 2.0
it works with my arc properly but not with the rear surrounds. might be the tuner as it does the same thing using the HDHomerun app. Maybe I should check in their forums as from this it looks like it should have worked..
It is normal for the Apple TV to send out PCM. It is still surround sound and should come out of the correct speakers. Did the surround sound test work or not?
It's possible that the way you are connecting your TV to your Sonos soundbar does not support LPCM with more than 2 channels. This can happen due to limitations of your TV's HDMI ARC, or due to using an optical connection instead of HDMI connection to your soundbar. The result is that LPCM audio is being converted to stereo somewhere between your Apple TV and your Sonos soundbar.
To fix this, try configuring your Apple TV to always output Dolby Digital.
Go to the Settings app > Video and Audio > Audio Format, then turn on Change Format. Then select "Dolby Digital 5.1".
Are you using Picture in Picture? I found that when I have PIP set to auto, and PIP engages, when I exit PIP and start another recording, I don’t get any 5.1 sound.
I also don’t get 5.1 on the HD homerun ap. I think their ap is messed up.
I am starting to think the cause of this is the homerun. I think for proper dolby digital 5.,1 or Atmos to work with my setup it has too be inputed over HDMI. I think the silicon dust tuner is not capable of this. Looking all over there site there is not mention of this. I have emailed their support for an answer.
While you really can't beat a tivo for dvr channels came close. dolby digital and tivo would be history
The hdhomerun captures the original broadcast in 5.1 Dolby. Playback depends on the streaming device and TV, but lots of users around here are getting full surround sound with OTA via hdhomerun.
What I bet is most do not realize they are not getting dolby digital. You would need to check the input of the device playing the sound. As I am trying to get the TV playing on the home theater setup. And it seems that true dolby digital output is not supplied from the tuner.
Now I am having same issue with homerun it must be there issue. But when you are sitting up home theaters you want the best sound. While the tivo supplies this the channels app does not. And I do believe this is the silicon dust issue.
I know I am capable of this as the Apple TV plays every other app just fine. But any app that uses that tuner has this issue.
Are you 100% sure you're not using a TVE channel, instead of one from the HDHomeRun? Seems too much of a coincidence that it's stereo.
What I bet is most do not realize they are not getting dolby digital. You would need to check the input of the device playing the sound.
No, most here aren't using Sonos' ARC/eARC solution - most have a receiver in the middle, so HDMI is chained straight through.
This isn't a fix, but what happens if you start a stream, and plug the apple TV's HDMI out straight into the Sonos? You obviously won't be able to watch anything, but if you can hear DD5.1 at that point, you have your answer.
Based on my own research and the thousands and thousands of complaints about needing to bridge TV audio to Sonos products, which finally spurred them to add HDMI in the first place, I would bet this is due to your TV bridging the audio, if only indirectly.
Not to pile on or anything, but DD is coming through fine here, OTA HDHR → Channels client on a Fire TV Stick 4K → Sony TV → Anthem receiver:
yeah - that's the issue with TV-based audio getting ARC'ed down - even a similar setup with a different TV may not work.
The problem is the arc standard is not required to pass 5.1. A lot of tvs will but are not required to, earc will however.
Can you cable the atv to your receiver directly?
I have an antenna hooked up to my Tivo, TV Tuner, and HD Homerun.
Tivo and ATV are connected directly to my receiver. TV audio is connected via ARC - my TV is 5 years old so doesn't have eARC
When I watch shows on Channels DVR on ATV, I get 5.1 as expected, exactly the same as I do on my Tivo or my TV Tuner. I get no 5.1 sound on when using the HD Homerun ap on ATV. But I do get 5.1 sound on the HD Homerun ap on my Roku, which is plugged in directly to my receiver.
I did hook my ATV up to my tv, and then back to my receiver via ARC. When using the HD Homerun ap, i DID get 5.1 sound, but it was on some channels which did not have 5.1 sound on my Tivo or TV (and these were sub-channels, which I know do not have 5.1). So I think via ARC my receiver was encoding the signal and incorrectly playing 5.1. Thankfully I don't have a way to add atmos speakers. Not sure how I would even do that with this set up 
Long story short, I think the HD Homerun ap for ATV is messed up.
As mentioned earlier, I get 5.1 fine from Channels, except when I turn on PIP. If i exit the Channels ap with PIP, when I come back to the ap (via closing PIP), I no longer have any 5.1, and have to restart the Channels ap.
Interesting about Apple TV 4K and PCM. My ATV is hooked up to my LG CX tv then to LG SN9YG soundbar, all via high speed cables and via eARC. Atmos (Netflix, Disney etc.) is fine but when I tune to an OTA channel through Channels the soundbar displays PCM.
If I use my Chromecast with Google TV in the exact same scenario the soundbar displays Dolby Audio.
TV is set to Pass-Through. I looked hard to try to find why I was getting PCM vs. Dolby Digital on the ATV, are you saying this is normal?
what I have come to believe is the arc soundbar is atmos and dolby 5.1 over HDMI earc and it does this really well. And the Apple TV does pass this.
But it appears the HDHomeRun can not do this. I have tried a new 4K HDHomeRun hoping the new tuner would help. It didn't
It seems that for dolby 5.1 it has to be over HDMI for my soundbar. The Apple TV does provide this. as well as Netflix and prime video . I was hoping to replace the tivo I use but it works properly.
Yes. ATV's don't pass-through bitstream audio for DD. It's an apple "it just works" quirk that many wish would go away, but aside from a volume level difference on most audio receivers, it's fairly benign.
