Apple tv4 7.1 surround not workin

Using the Auto setting on audio out actually seem to produce correct surround sound on my system. Can it be that in the Auto setting actually makes the ATV4 do the decoding (irrelevevant of it being a 7.1 or 5.1 Dolby digital coded movie)?

Hello, this is what are my findings (already posted in other thread)

Just installed the Home Theater test App (thanks Bodosom).

When having the surround setting set to 'auto' the receiver detects 7.1 PCM input 3/4/.1.

THe App detects 8 speakers, so far so good!

THen however during the test all speaker signals are mixed up. Rear channels direct to subwoofer, left surround to center etcetera. Two out of 8 channels do not produce any sound.

The App hints to a problem of mixed signals. Workaround would be to set the Dolby Digital setting to 'ON'. However this setting does not exist in ATV 4.

when setting the ATV to surround mode 'auto', the App only detects 5 speakers.

HELP!

Roggamannen wrote:

Can it be that in the Auto setting actually makes the ATV4 do the decoding (irrelevevant of it being a 7.1 or 5.1 Dolby digital coded movie)?

I initially thought the ATV 4gen was decoding everything and sent PCM. This is because my AVR has both OSD and web interfaces and reported two different values for the input signal from the ATV 4gen. It's now clear that when Surround Sound is set to Dolby Surround an AC-3 signal is generated however the bitstream from a model ATV5,1 (ATV 4g) is not the same as the bitstream for the same input a model ATV3,1 (ATV 3g). The "dialnorm" meta-data has been removed which means it is modifying the bitstream. I don't know if it's possible to do that without a decode/encode step.

The critical part of this for this thread is that the ATV 4g is decoding everything in AUTO mode it's not possible to know what the original bitream contained. Since we have a report of rear surround data in Terminator Genisys we can conclude the data is there. I don't imagine we actually need to compare a disc version to be convinced that Apple is putting one over on us.

Despite the OP rather vehement assertions about this after you consider the possibility of multiple audio tracks and the ATV 4g picking AAC rather than AC-3 I think that

1) The jury is still out if there's are bugs relevant to this thread.

2) If there is a bug or bugs I'm sure fixes will be forthcoming.

3) If there isn't a bug Apple will change the way it works so to minimize support calls.

@bodosom Good Analysis, thanks for that. Could you emphesise on how this relates to channels being mixed up when using that Theater App?

bodosom wrote:

... a model ATV5,1 (ATV 4g) is not the same as the bitstream for the same input a model ATV3,1 (ATV 3g).... Apple is putting one over on us.

sigh

That should say "ATV5,3" and "Apple isn't putting"

jvulto wrote:

@bodosom Good Analysis, thanks for that. Could you emphesise on how this relates to channels being mixed up when using that Theater App?

Buggy software. It would be nice if the developer fixed it but I think the presence of reasonable rear surround data in Terminator Genisys is sufficient validation that 7.1 and E-AC-3 are working.

Discoslap wrote:

Bodosom, please play terminator from Blu ray than try Apple tv4 and you will realize very fast it's totally different.

Reasonable content has been reported for the iTunes version.

You've done this comparison and found a difference you can attribute to improperly encoded E-AC-3?

In my case even if I was interested in buying two copies of a wretched movie for testing purposes and was willing to reconfigure my HT with rear surrounds I wouldn't be surprised if TrueHD sounded perceptibly different from E-AC-3.

Receiver surround mode: auto

ATV surround mode: auto

The home theater app does mix up signals but also two of the signals are NOT hearable.

When playing Terminator G in 7.1 sound track, all channels work correct (not mixed, I think) but back surround L+R NOT hearable.

In both cases the receiver shows as input signal: 3/4/.1

Home Theater app not being able to produce sound for two out of 7.1 channels seems like the same problem when playing Terminator G in 7.1.

The mixed channels thingy probably is a bug of the app itself, but the missing two additional channels does seem to be a ATV overall issue.

When playing Netflix content with DD+ also the two back surround L+R NOT hearable.

jvulto wrote:

The home theater app does mix up signals but also two of the signals are NOT hearable.

When playing Terminator G in 7.1 sound track, all channels work correct (not mixed, I think) but back surround L+R NOT hearable.

I don't have rear surrounds configured so I can't directly contribute but see this AVS post.

What is this home theatre app that everyone is using.

What is this home theatre app that everyone is using.

It's an app available in the TV4 App Store.

7.1 Definitive not working on AppleTV4 !!!

5.1 works fine!

Tested with Plex, Simple X and some other DLNA Players!

Some different movies, PCM, DD, DD+, etc...

Even if it shows 7.1, 2 channels have no output...

5.1 works fine...

So far i can say till now, i love apple products, but the ATV4 is the worst invest I've ever did!

Any Android with Kodi makes a much better use! 7.1 / 24p / 3D Movies / 4K and more...

Now this thing lies here around, i can return it or hope for updates...

Maybe i will use the box for games... but i have a PS4...

But for movies, ATV4 is crap... So i hope for updates, specially for 24p / 30p and the promised 7.1 playback.

Ah and yes, please apple, there is a built in cec... Please add 3D Video playback with auto CEC tv mode switch...

Just my 5cents

Cheers :-)

After getting off the phone with Apple they released a software update today. hopefully fixed this