[djcorvus]

Hi guys,

This problem has been driving me insane these past few weeks.

I have certain .mkvs - all encoded in either Dolby Digital or TrueHD, some which play back fine in BOTH Windows Media Player and Kodi (Krypton) in Dolby Digital (my receiver correctly displays Dolby Digital in both cases), but some .mkvs ONLY output Dolby Digital to my receiver through Windows Media Player - Kodi just outputs stereo. The only difference I can find is that these files are encoded in Dolby TrueHD, which my amp does not support.

I've tried all manner of combinations in Kodi settings, from switching between 'fixed/optimzed/best match' and either HDMI or WASAPI drivers. I've also ticked and unticked some/all combinations of audio codec output under WASAPI - nothing works.

All under bitstream, of course.

It seems for these certain files, Kodi wants to either output in Stereo, or no audio at all, unless that file is SPECIFICALLY encoded in Dolby Digital or regular DTS.

If I turn off bitstreaming within Kodi, I still get stereo, even if I manually select my speaker config to 5.1.

How the HELL do I get Kodi to output Dolby Digital from this files to my amp, just like Windows Media Player does??

[Karellen]

Can you provide screenshots of your Settings>System Settings>Audio pages

Upload to https://imgbb.com/ no account required.

You will need to provide a debug log. The instructions are in my signature. Use the Basic method. Once you have enabled debugging in Settings>System Settings>Logging, restart Kodi then replicate the problem. In your case, try to play the movie. Once done upload to pastebin and link back here.

[Powerhouse]

Try the following...

From my own personal notes (some of which were copied from other posts found throughout this forum)...

- The number of channels can be left to 2 (which is Stereo, but read below the Enable pass-through part).
- Output configuration change to Best Match (If you notice sound issues, change to Optimized).

Best Match

This looks at the audio properties of the file and picks the output format that most closely fits those properties out of the supported formats your device reports to Kodi.

Benefits - If your device supports all the audio for formats contain in your files then it's to get works called "bit perfect" through, in laymans terms what we send exactly matches what we receive from the files, so 5.1 in for example will always result in 5.1 out.

Downside - each time the properties received from the file changes then the audio system needs to be reinitialised with those new properties and some hardware does like this, so may result in very small audio drop outs as the hardware such as AVR copes with the change in what Kodi sends.

Optimised

This minimises changes in the audio properties of what Kodi sends, so it won't always exactly match the properties of the file, so in a playlist of files we take the properties of the 1st file and that is used for all subsequent files in the playlist even if they have different audio properties.

Benefits - for hardware sensitive to audio property changes this minimises the chance of things like audio drop outs.

Downside - If watch a live stream, if when you start watching it's send 5.1 then that is how audio is set up, if during a commercial break audio changes to 2.0 then we still send 5.1 , alternatively if you start watching during a commercial break with 2.0 audio then the TV show starts it's 5.1 then we still send audio as 2.0

Fixed

This is only available for audio we decode for sending as PCM as we must always have the ability to resample the audio. This is used where where hardware is sensitive to any change in audio properties, or the hardware does not perform well with certain sample rates.

Benefits - audio should always be playable without any audible issues.

Downside - not possible with passthrough audio, and depending on the audio properties of your files could result in audio being resampled a lot of the time.


- Stereo upmix should be OFF
- However, you can enable Stereo upmix, it just outputs stereo sound to all speakers instead of the front. May be useful if you have to crank the volume to hear people talking. However, if you have a Receiver, don’t enable this feature.
- Maintain original volume on downmix should be ON
- Keep audio device alive can be set to 10.

The 'Keep audio device alive' setting keeps the audio device alive at the Kodi end, so where we need exclusive access to the audio device we maintain a lock on the audio device or other programs can't grab access from underneath Kodi. This is mainly an issue with Linux and Windows audio systems, I don't believe it's possible to get exclusive access on Android.

The 'Send low volume noise' setting ensures an active audio stream is sent to whatever external device you use for generating the sound (TV with speaker or AVR with speakers) as some hardware will drop the audio connection if it does see any incoming audio, this then prevents the possibility of the very start of a audio stream not being heard while the audio connection gets started backup. The 'Send low volume noise' setting is optional because although the noise pattern is done in such a way it should never be audible so all the human ear should hear is silence, however in practice some external hardware may alter what it received and end up producing some audible effect that the user can hear and may not be very pleasant.

- Enable audio DSP processing should be OFF
- Enable pass-through should be ON if you have a Receiver.
- If you are connected to a Receiver? Then change the settings to use Pass-through. Also, the recommended “number of channels” settings is 2.0, even if you have 5.1 or a 7.1 surround sound setup. Because not all Receivers will accept pass-through if it’s set to 5.1. Even then, because Kodi is using a “hacked” method for passing audio over HDMI, pass-through doesn’t always work or work correctly with certain Receivers. The only reason to set it to 5.1 is if Kodi is doing the decoding and you are sending LPCM to your Receiver (this means that Kodi is doing the decoding and sending the decoded audio to your Receiver).

Settings>Player settings>Videos>"Sync playback to display" should also be set to off.

Also look at this thread...
https://forum.kodi.tv/showthread.php?tid=311370

[djcorvus]

Try the following...

Thanks, I've already got all those settings as you've described anyway - so obviously they are not the problem

Can anyone suggest anything else?

[djcorvus]

So I just opened Kodi to do a debug and noticed that my channels were still set to 5.1.
Weird, because I could've sworn I set it back to 2.0 a while ago.
Anyway, I set it to 2.0, and now it works!

Goddamn, to think it was such an easy fix all along! I really hope they've ironed out that bug in later versions, it was driving me nuts!

Thanks for all the help.

[foghat]

Weird. Pretty sure if pass-through is enabled, it shouldn't matter what you set the speaker config to.

[Powerhouse]

Not weird at all, as I said above "Because not all Receivers will accept pass-through if it’s set to 5.1".