Apple TV 4 not outputting AC3 track as Dolby Digital

I have that, but thats not solving the issue as I said. It's a workaround not a fix and I personally would rather use the atv4 as is, otherwise I'd be using a roku and a windows pc or something.

Either they have screwed up the system and they need to fix it OR they have changed something in the code regarding placement of soundtracks or added a new tag to mark something as 'DD' that makes the way we mux them in programs such as iFlicks or Subler fail where before they worked.

It's not that the atv 4 CANT output ac3 Dolby Digital - it does for netflix and for purchased media from the iTunes store. It's that something has changed either in iTunes or their own ATV4 coding that makes our files incompatible re the DD tag.

That is what needs sorting and maybe theres a dev guy here who knows something about this and can shed some light?

I have read in some places that the atv4 is actually designed to decode the DD signal and pass through the resulting PCM multichannel audio with all the decoding already done...with the ATV3 the box only passed the signal along and did no processing of any sort. I imaging this is why apps like plex and infuse can send the ac3 DD signal through - they just don't decode anything and pass through things as they are.

That said, this still means that somehow the ATV4 box CAN decide to NOT decode the DD signal with iTunes store content and pass it through ala ATV3 and only does decode for 100% of the time with homeshare files...so I think there must be some tag or header/meta in those iTunes store files that marks it for forced passthrough rather than forced decoding. I hope some devs figure this out and find that flag marker so we can add it into mixing progs.

I wouldn't have such an issue with ppm multichannel but DD sounds so much deeper and vivid and the pcm multichannel sounds to my ears - not as good - because it lacks that boom and crispness. Perhaps some equaliser fiddling can fix this 😟

BTW< SuperSizeIt, no offence or rudeness was meant in my reply to you. I just really want someone to look at this and get to the root of it but its probably a long shot and i either have to get used to multichannel pcm or use infuse for the DD passthrough.

Or buy everything through iTunes store...convenient how iTunes store content i.e. things you have purchased from Apple give DD signal without an issue...

Hello TidyGraphic 🙂

I do think there is something in these files with the coding, if the atv4 can output a DD signal without processing it first (DD once processed by the ATV4 becomes pcm multi stream i believe) for netflix and iTunes store then surely they can do the same or enable an option to send audio out without processing fullstop so homeshare files are DD again.

The problem Iv personally had is that many people either don't seem to have a receiver than decodes ac3 DD so don't see the pcm multistream as a problem but as a positive (since this means the atv4 is decoding it for you before it send it out) or those that say 'well i have surround sound so its ok' and ignore that fact that yes we have surround sound but its not all the same. I think most people with a receiver worth £500+ would much rather that does the audio processing than a £129 box and since atv3 allowed you, and netflix and store content still lets you do this on atv4 why not homeshare 😟

Re your soundbar thats a weird one! It does remind me of issues iv had with bluetooth earphones in the past but I will have to read your post again and have a think.

No prob messaging here matey, who knows someone might read this thread and know a solution to your problem 🙂

Hello Dolby Digital fella!! Or lady of course 🙂

Firstly I gotta thank you for that page - that's a real help to a lot of people and a shame apple couldn't have made a page for these things themselves knowing a lot of people might have these questions lol. Ill try to link to that page in a few forums if thats ok by you and give you the credit in there.

So from what I read I am concluding that my thoughts were right and pcm multi stream is sorta here to stay. Not necessarily a bad thing as such but perhaps something the ear has to get used to in my case (i miss that something special that the receiver did to sound when it was the thing decoding DD) and I suppose I have to look upon it as just an evolution of the audio for 7.1+ sound.

One thing I find odd - maybe you can advise me here - is that the 'DOLBY SURROUND' function doesn't work for me on homeshare (i.e. files I stream from itunes on my mac to the ATV4) 😟

If i enable that option netflix and iTunes store things are indeed seen by my receiver as 'DD' but my homesahre files seem to fall back to 2.0 sound (either the aac 2.0 track or the 5.1 ac3 track down mixed, i can't tell) rather than DD 5.1

I say odd because my receiver accepts and decoded just about every format of sound there is and never had a problem with DD signals from anything else but the atv4 and homeshare.

Anyway, thats either bug they will fix or not and as you say, multi stream pcm = 5.1 just pre decoded and mixed and the main thing is that the surround sound IS there in some form.

So, in conclusion, thank you very much for that help! Its a weight off my mind to know what is and isn't going on!

Hope you see this reply 🙂

Warmest regards,

Chris.

Just further to what I wrote earlier, I read a hilarious article on the placebo effect of listening to pcm multistream whilst wanting with all your heart to see that red DD light up on your receiver lol. Thats so me 🙂

Just a further update to anyone following this:

Today I rebooted my ATV4 via the menu after a weird audio came though on the home screen that i couldn't identify. Sounded like a popup for timeshares lol.

I was planning to watch netflix so set the sound to 'dolby surround' to force it through.

Decided to check a file from homeshare was in sync before I started my season binge...ac3 Dolby Digital came through to the receiver.

Checked other files under movies, some tv shows, all working and sending ac3 Dolby Digital.

I have no idea why this is suddenly working, iTunes hasn't had any updates the past week, neither has the tvOS software...

It may be a glitch that if ac3 DD doesn't get forced through we need to restart the atv, i really can't say, but it is definitely working.

Beautiful red DD letters are glowing at me.