Bargain If you have problems playing back certain MKVs (e.g. w/TrueHD or FLAC), read this


Novice Member
Hey :)

Just discovered this the other day, and felt like I had to share it.

On the built-in media player on my OLED B6, both using external HDDs and DLNA, I've had some "stubborn" MKVs that just refused to play, even though they worked fine on any other software player that I have.

I already knew that my TV wouldn't play back Dolby TrueHD, but it's only during these christmas days that I finally made the connection between certain audio formats and the inability of the TV to play back the MKVs. Part of this delay in my discovery is that these files that fail to play back may contain incompatible audio formats, but I'm making sure to also include compatible formats alongside them, so when they've failed, I've thought it had to do with something else.

It's somewhat related, I think, to that strange message, "Only video will be played back, audio not supported" (something to that effect), even when it's just talking about one audio track, and the other(s) will play back fine.

What I've found is that if the first audio track in an MKV (or any other container, I assume), is unsupported, the file fails to play back completely. So, if your first audio track is TrueHD 7.1 Atmos, and the second one is DD 5.1, the file won't play back. At all.

But, if you remux that file (mkvtoolnix FTW), changing the audio track order so that the first track is a compatible one, it'll play back just fine, using the DD 5.1 audio track and ignoring the incompatible one(s).

An additional bonus to this, for me, is that the unsupported (AFAICT from the LG list of supported audio formats in MKVs) format FLAC is actually supported! But, you still have to move or create a supported format in front of it to get the file to play (if it's first, it'll fail completely). I have spent a day or so ripping my Criterion Collection BluRays, and this was just a life-saver for me. I've just created MP3s of LPCMs or FLACs, and muxed them in before the incompatible audio track.

I hope this helps anyone. It's super useful to me, anyway :). Oh, and if this is sorta mumbojumbo to you, then just try getting the "MKVToolNix" app - it's free as in beer and speech, and available on pretty much all platforms. Find a guide on the intermcwebs, and you should easily be able to find out how to remux any existing troublesome MKV to get a compatible audio track hoisted to the top of the list.



Distinguished Member
Why not just build a Plex library and connect your MKV files to it? Plex will give you the ability to manually select any of the audio tracks included.
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