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I've searched these forums and although I've seen some postings with some issues with AC3 I could not find anything pertaining to AC3 and the AppleTV.
Running my movies on my AppleTV through say ATVFiles, my Handbraked files play fine. Movies with an AC3 track switch my 10 yr old Yamaha receiver (hooked up through toslink cable to ATV) into Dolby Digital surround sound as soon as they start. Yet when I try to use XBMC on my AppleTV all I get is stereo sound (or no sound as detailed below).
In System/Audio Hardware I've made sure the Audio Output is set to Digital and I have both Dolby Digital (AC3) Capable Receiver and DTS Capable Receiver selected (I've also tried both separately). Audio Output device is set to Built-in Line Output (only option).
When a movie starts, and I see/hear no surround sound) I pull up the Audio setting and while the Audio Output is set to Digital the Audio Stream is set to English Stereo (w/stereo sound coming through my speakers). If I change this setting to English-AC3 5.1 I then get no sound (and my stereo indicator doesn't change either).
Other notes:
- These movies are ripped with MTR then encoded with Handbrake with the AppleTV preset including AC3 + AAC audio.
- As I said previously these play fine on both my AppleTV through my stereo in AC3 and on my MBP in stereo AAC.
Thoughts? Ideas? Thx
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i get the same problem too... no sound, and i double checked my settings... i am using a 720p mkv file with AAC+AC3
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d4rk
Team-XBMC Developer
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Please post the log file located at ~/Library/Logs/xbmc.log to pastebin.com and provide a link here.
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d4rk
Team-XBMC Developer
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It looks like there's definitely an issue passing through AC3/DTS specifically on the Apple TV. The issue is not related to your receiver. It needs further investigation. Most likely related to how PortAudio handles ATV's audio device.
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I believe the decoding of AC3 does infact work
The issue lies in the fact that the AAC audio is track 1 and AC3 is track 2. XBMC by default appears to be selecting track 1. Which is of course the AAC 2 channel file. We need XBMC to auto detect the AC3 file (track 2) if the Dolby Digital passthrough mode is enabled in the settings for xbmc. I have messed around with this alot and I see no way of getting XBMC by default to use track 2 without either manually selecting it while watching a movie or to reencode all my files and not have the AAC file be part of my m4v file. Or if you reencode the m4v file make sure the AC3 is track 1 and AAC is track 2. I have some movies for some reason have the AC3 as track 1 and I can tell on my reciever that its decoding the AC3 track. For all other movies if I manually select track 2 my reciever see's the AC3 track and decodes it just fine. Hope my findings will help in solving this huge problem.
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matt: I have tried to encode with just ac3 audio using Handbrake 0.9.2 for windows. (resulting in an mp4 file) using the Apple TV defaults + 2 pass encoding.
I have also tried encoding with Apple TV defaults (AAC + AC3 in an m4v container).
I am getting similar results to tuck. AAC track will play fine (xbmc labels it as stereo). AC3 track plays video fine, but audio is silent. Tried Digital and analog outputs with no luck.
AC3 in an .avi container plays fine.
Any other information i can provide that may help? (Using latest version of t3ch and mediastream 10-13-08)
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igeekus:
Have you verified that you have a good fiber optic cable connected to your receiver? Have you tested it with a DVD player? What reciever are you using to decode the audio?
I myself have actually broke the fiber cable by accidently bending it to much.
That is one thing I would try. If it works with a DVD player then I guess there is something wrong with your particurlar amp recognizing the signal. From my understanding the audio coming from the fiber optic port is a RAW AC3 signal which any reciever today should be able to decode with no problems at all.
Are their other users on here that are having the same problem as you?
Does anybody else have problems decoding AC3 from a movie when the settings on the apple tv have digital out enabled?
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Additionally, what version of XBMC are you using?
I see you put (Using latest version of t3ch and mediastream 10-13-08)
at the end of you reply.
Are you using xbmc beta 2 atlantis on an apple tv?
I think the t3ch versions were only released for the original xbox.
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Why are you posting this in the appletv/OSX Forum?
Should this not be posted in the original Xbox Forum?
The .avi and .m4v containers can't be interchanged. If you rename the file it will not work correctly. I have no idea why it is not working for you on the original xbox. I only have an apple TV and everything is working fine for me except for the fact that I have to select the AC3 track in order to get the surround sound working. Additionally, handbrake does not "encode" AC3 it takes the raw audio right from the DVD and puts in in the M4v file. Also XBMC does not decode the AC3 audio it passes the RAW audio from the m4v file and then the reciever does the decoding for you. Somebody in the xbmc xbox forum may be having issues that you are having. Maybe it is a bug in the xbox version of the software. I am not really sure. A developer may be able to tell you more. But you are correct in stating that if the 5.1 audio from an avi works then its not your hardware.
You may try and tweak your settings in handbrake and not use the default appletv settings. I know if you search on here or the handbrake forums you can find the recommended settings for use on the original xbox. The original xbox does not have as powerfull hardware as the appletv. If you use the appletv preset you may run into problems with frames skipping in your movies, etc.
Also, why don't you just use the avi container since its working for you? the m4v file contaner was specifically made for the appletv. (pretty much the same as the .mp4 extension).
Best option if I where you, is to use the .mkv extension because that allows for chapter support. Don't know if the chapters will work in xbmc but the mkv format allows you to do chapters which the .avi container does not. I think you can use .mkv with ac3 audio in handbrake.
