Nvidia shield audio missing on playback

[rfischman 1]

Trying to playback a video - Chicago Med. Audio is missing when initiating playback. Codec says it is dolby. Device is directly connected to tv and there are no options to change from anything other than pcm.

 

If i select the playback correction option the apo corrects the missing audio and the codec showd as aac.

 

Logfile was sent from the emby app on nvidia shield at 0740 eastern daylight time. Show name is chicago med and user logged in wsd Reuben

 

As an additional bit if i use the emby app on the tv directly audio is fine

Same when using the app on an android phone or the emby theater on windows

[ebr 14955]

Hi.  What is the device?

 

Have you tried setting the app audio setting to "Downmix to Stereo"?

[rfischman 1]

Yes. Ive got two different setups both exhibiting the same issue after more experimenting this morning.

 

Original report was from a shield connected directly to a samsung smart tv tizen based. Dont recall exact model

 

Tested on another setup which has shield connected to a yamaha receiver connected to an lg tv. Both the lg and yamaha are less than 3 years old.

 

On the setup going through the receiver, the exact same behavior is observed. no audio until choosing playback correction and then instead of trying directplay it transcodes to get the audio to an aac codec with a reason of container unsupported.

 

Also tested on the exact same receiver and tvs using appletv and that worked fine.

 

The video being played back was live recorded and them converted to mp4 using mcebuddy. The profile used was mp4 unprocessed which should only have changed the container. The original mpeg2 stream plays fine but is transcoding on playback by default

[rfischman 1]

I've been doing some more tinkering and it seems to be something to the emby app on Android TV.  Web based player, emby theater on windows, and the emby app on android, iPad, and the TV sets are all properly transcoding the audio without having to select the "Playback correction" option.

 

For comparison, I also fired up the plex server and tried the same video through that server.  The android TV app for plex also properly transcodes the audio.

 

Hope this, and the logs I had the android app send earlier help point in the direction.

 

I also tried using MCEBuddy to transcode the original mpeg2 stream into the MP4 Normal profile, which converts the audio to AAC automatically.  That does playback correctly across all platforms and apps with emby, but occasionally I get some chop in the conversion.  Was hoping to use the unprocessed profile to just change out the container but I'll be sticking with the one that converts the audio for now.

[ebr 14955]

There is something odd about this encode.  The player is not seeing any audio track at all:

03-30 07:41:00.037  5885  5885 D EventLogger: tracksChanged [0.35, 0.00, window=0, period=0, 
03-30 07:41:00.037  5885  5885 D EventLogger:   Renderer:0 [
03-30 07:41:00.037  5885  5885 D EventLogger:     Group:0, adaptive_supported=N/A [
03-30 07:41:00.037  5885  5885 D EventLogger:       [X] Track:0, id=1, mimeType=video/mpeg2, res=1920x1080, supported=YES
03-30 07:41:00.037  5885  5885 D EventLogger:     ]
03-30 07:41:00.037  5885  5885 D EventLogger:   ]
03-30 07:41:00.037  5885  5885 D EventLogger: ]

Can I please see the media info from the web app for this item?

[rfischman 1]

Yep.  Here's a screenshot of the media info..

 

Also attached the "Stats for nerds" screenshot when playing it back in the web player.

 

 

[ebr 14955]

The web player has to transcode this due to the video codec so that's why that is working.

 

Ffmpeg is finding the audio track but the Android TV player does not see it at all.

[rfischman 1]

And my Apple TV with Emby is also properly playing back.  Do you want the info from its stats for nerds as well?

 

Also, is there any way for me to get you the actual media file for testing/debugging with the android tv player?

[ebr 14955]

If you can dropbox it or the like and PM me the link.

 

Also, you said you were creating these with an external program.  You might look at the settings for that and see if there is anything odd there.

[rfischman 1]

Will do.  I'm using MCEBuddy to do the transcoding on the MPEG2 streams.  The "Unprocessed" settings claim all they do is repackage video/audio into the MP4 container without touching the original audio or video source.

 

And for comparison, here's the media info from the original MPEGTS container.  the only difference I can see is the "Default" setting on the audio track.  Will see if I can change that in MCEBuddy and see if it makes a difference.

 

I'll try messing around with changing the audio track "default" setting and if that doesn't make a difference, I'll drop box you the original and converted.   However, in looking at a file that I used a different conversion profile on (changes video to H 264 and Audio to AAC), it also has the default track flag set and works fine..

 

 

 

 

[Luke 37220]

Is mp4 intended to hold the mpeg2video codec? It's not a combination you see very often. You may want to consider having mc3buddy repackage to mkv instead.

[rfischman 1]

Thanks Luke.  I just tried converting to MKV and it resolved the missing audio.  It also resolved some stuttering video/audio issues I was having on some channels with the raw .TS files.  Even with the MCEbuddy converstions to MP4 holding H264/AAC I'd still get some stutters or out of sync audio/video.  The MKV unprocessed conversion handled that as wel.

[Luke 37220]

Thanks for the feedback.