Audio not working with MKV containing DD TrueHD stream

Hello,

I have re-muxed some streams from a  blu-ray film I have, into a Matroska file. The audio is DD TrueHD.

While the file plays with no issues on my PC with only the CCCP software installed (I’m guessing it simply extracts the AC3 core), I cannot get it to play on the WDTV Live I have.

The video/subs are fine, but there is no audio at all. When selecting the audio stream, the player identifies it as a “DDTrueHD (Digital)” stream. I’m guessing the “Digital” part means the player is attempting to simply bitstream the audio.

I understand the WDTV live is not capable of decoding the new lossless HD audio formats. However, why is the unit not simply extracting the AC3 core audio? It works fine with DTS HD-MA tracks in other MKVs I’ve created from blu-ray rips. The player seems to identify the DTS core and plays this (“DTS” is shown as the audio type).

Is there any way to simply force the player to decode only the AC3 core audio, as opposed to automatically attempting to bitstream the whole stream?

I’d greatly appreciate any advice.

Thanks,

Odai.

Yes, remux your files to only have AC3 audio.

Hello, Sorry to bump this - been very busy and completely forgot about it.

I would prefer to keep the original HD audio stream, as the MKV is on a network drive, and is accessed also from PCs on the network. I use software on my PC that is capable of decoding the TrueHD audio, so it would be a shame if I had to strip the HD audio on any Blu ray rips I make that have TrueHD as opposed to DTS MA.

What I don’t understand is why the DTS HD audio works fine, the player simply picks up on the core, but insists on forcing a digital passthrough on the Dolby HD audio instead of decoding the AC3 core. Am I missing something? 

It must extract the 5.1 core from DTS-HD MA because the WD does not have a license for DTS-HD.

It does NOT need to extract the AC3 core from Dolby Digital True-HD…  It will bit-stream it as-is.

If you don’t have a DD TrueHD capable amp and need AC3, just be aware that not all DD TrueHD tracks are interleaved with an AC3 “core”. Another factor could be the software being used to convert the movie into MKV.

Ideally, you should try to create an MKV with separate AC3 and TrueHD tracks.

hi there

for testing purpose link :  http://www.demo-world.eu/trailers/high-definition-trailers.php  [various demos to test audio/video] 

regards

pawson

Thanks for all the responses guys.

I did think the issue was down to the HD track possibly not containing an AC3 core, but this is not likely to be the case as the file plays fine on all my PCs (none of which are capable of decoding HD audio).

For the time being, my workaround is simply to make a copy of the audio stream, downconvert the copy to AC3, and mux both back in to the file.

However, it would be ideal if a fix could be implemented for this. As the capability to decode AC3 is already there, wouldn’t it just be a firmware tweak? So that the player would default to decoding the AC3 core instead of defaulting to bitstreaming the whole thing? Or at least give us the option to do either?

Quite a few blu-rays have TrueHD audio, it would be a shame to have to go through the hassle of including both tracks with each rip. Not to mention the additional space it would take up. :stuck_out_tongue:

DTS-HD Audio consists of a backwards-compatible 5.1-channel core, but Dolby TrueHD (being based on MLP) is not backwards compatible with Dolby Digital Plus/Dolby Digital. So don’t request WD Live/Live + to extract the AC3 core from TrueHD.

Not sure what kind of tools you use for bd ripping but here is an app that can

Rip Blu-ray to MKV (BD ISO/BDMV/physical BD supprted);

Convert PGS to VOBSUB subtitles;

Downmix TrueHD/DTS-HD to AC3 5.1 audio.

In this way video, audio and subtitles should get played properly. 

Download(note this is trial of shareware- Windows)

Guide

I am able to use TrueHD only when the audio is set to manual passthru with the appropiate boxes checked and only when I use my NAS running twonky server for both mkv and m2ts files. If audio auto is selected or I access the shared NAS directly TrueHD will not play. I have used several programs to make the m2ts into a mkv and the audio stream is still available only when served audio manual via twonky.