Problem with Dolby Digital sound
#1
Hi

I'm having trouble getting 5.1 sound from files encoded in Dolby Digital or Pro Logic II on my Qnap ts-469L.
Basically even if I enable Dolby Digital capable receiver in xbmc, the receiver doesn't recognise it as such and plays garbled sound or nothing at all... it only recognises the Dolby Digital signal (DD light turns blue).
Interestingly enough, DTS causes no problem at all and is played in its full 5.1 glory.

Mind you I have an old receiver (Sony STR-DB940 QS). But it is fully Dolby Digital capable, and DVDs work perfectly in 5.1 Dolby Digital.

I'm using this audio extractor to get the image through HDMI to my projector and the sound through optical to the receiver: http://www.amazon.co.uk/gp/product/B00A ... UTF8&psc=1

Now, do you know if there are any restrictions on the QNAP side when it comes to passing through the Dolby Digital sound? Is there any way I could encode my DVDs to get 5.1 sound to play? I currently use the custom audio output device values "plughw: 0,3" in xbmc. The Qnap forums aren't of any help so far Sad

Essentially if you read the above, you'll notice I have no idea where the problem actually is...

Would appreciate any help, really!

Xbmc Eden 11.0.2
Qnap QTS 4.0.2
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#2
I have exactly the same problem and i have tried alot of settings.
Try to read my topic: http://forum.xbmc.org/showthread.php?tid=171187

I will keep an eye of this topic!
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#3
Here's the logfile, by the way: http://xbmclogs.com/show.php?id=47617

Is there a way to manually set AAC Passthru as 'enabled'? Could that be an issue? Basically I've noticed that sometimes I can hear full surround sound for a fraction of a second before the blue light and 'Dolby Digital' logo appear on the receiver. Then all goes silent. So something is suppressing the sound on the digital signal or so...

Really need some help please :-(
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#4
I found that many people were experiencing this exact issue with Boxee: http://forums.boxee.tv/showthread.php?t=21990
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#5
Code:
20:19:06 T:139696529192704   DEBUG: Initialize - using alsa device plughw:0,3,AES0=0x6,AES1=0x82,AES2=0x0,AES3=0x2
20:19:06 T:139696529192704   ERROR: Initialize - failed to open custom device plughw:0,3,AES0=0x6,AES1=0x82,AES2=0x0,AES3=0x2 (error:No such file or directory), retry with default plughw:0,3

a plughw device with software mixing for passthrough is not okay (only some nvidias (ancient ones) work like this).

Get me:
Code:
aplay -L
aplay -l
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#6
Danke fritsch!
I'll try that asap this afternoon when I'm back from work. Apologies, I'm a total newbie at Linux, do I just enter these commands in the console?
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#7
yes
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#8
hmm it tells me: -sh: aplay: command not found

I figured I probably had to download it... so I found alsa-utils and downloaded the package. Where should I put it so that I can make them work?
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#9
No idea how qnap handles this. Use their package manager if they have one. It is not xbmc related.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#10
Ok found it... Managed to install alsa-utils using Optware IPKG addon.

Gave it another go:

[~] # aplay -L
null
Discard all samples (playback) or generate zero samples (capture)
[~] #

and

[~] # aplay -l
aplay: device_list:235: no soundcards found...


is it bad, Doc?
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#11
:-) yes, it is. No idea. That part is not a xbmc problem and I don't know how QNAP handles it.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#12
Oh bummer. Qnap doesn't handle anything with passthrough. :-(
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#13
I wonder if it could be a problem with the encoding of the file in Handbrake... Although I select AC3 passthrough, could it potentially be that some PCM or whatever dodgy signal still gets through?

Is there a way I could encode a DVD (video+audio) and make sure the audio track is completely unaltered?

Alternatively I'm going to test playback of an encoded file using the Qnap Multimedia Station and maybe also Plex. But I suspect the problem will persist.
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#14
makemkv doesn't re-encode anything.
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