Audio re-muxing in the app but not in WebOS browser

[zsohu]

Hi,

I'm using the "new" app from the store (thanks for getting it there!) at the moment but the same happened with the one I installed with the developer mode. My LG C9 is running the latest WebOS available.

My issue is that I can't play certain audio tracks in mkv containers without re-muxing/transcoding using the app, however if I open the WebOS browser and use Jellyfin from there all the tracks are direct playing.

Example file where the issue happens:

Format                                   : Matroska
Format version                           : Version 4
File size                                : 7.06 GiB
Duration                                 : 1 h 0 min
Overall bit rate                         : 16.7 Mb/s
Frame rate                               : 23.976 FPS
Movie name                               : 
Encoded date                             : 2024-03-21 11:06:24 UTC
Writing application                      : mkvmerge v82.0 ('I'm The President') 64-bit
Writing library                          : libebml v1.4.5 + libmatroska v1.7.1

Video
ID                                       : 1
Format                                   : HEVC
Format/Info                              : High Efficiency Video Coding
Format profile                           : Main 10@L5@Main
Codec ID                                 : V_MPEGH/ISO/HEVC
Duration                                 : 1 h 0 min
Bit rate                                 : 15.3 Mb/s
Width                                    : 3 840 pixels
Height                                   : 2 160 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 23.976 (24000/1001) FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 10 bits
Bits/(Pixel*Frame)                       : 0.077
Stream size                              : 6.46 GiB (92%)
Default                                  : Yes
Forced                                   : No
Color range                              : Limited
Color primaries                          : BT.709
Transfer characteristics                 : BT.709
Matrix coefficients                      : BT.709

Audio #1
ID                                       : 2
Format                                   : E-AC-3
Format/Info                              : Enhanced AC-3
Commercial name                          : Dolby Digital Plus
Codec ID                                 : A_EAC3
Duration                                 : 1 h 0 min
Bit rate mode                            : Constant
Bit rate                                 : 640 kb/s
Channel(s)                               : 6 channels
Channel layout                           : L R C LFE Ls Rs
Sampling rate                            : 48.0 kHz
Frame rate                               : 31.250 FPS (1536 SPF)
Compression mode                         : Lossy
Stream size                              : 277 MiB (4%)
Title                                    : DDP5.1
Language                                 : Hungarian
Service kind                             : Complete Main
Default                                  : Yes
Forced                                   : No

Audio #2
ID                                       : 3
Format                                   : E-AC-3 JOC
Format/Info                              : Enhanced AC-3 with Joint Object Coding
Commercial name                          : Dolby Digital Plus with Dolby Atmos
Codec ID                                 : A_EAC3
Duration                                 : 1 h 0 min
Bit rate mode                            : Constant
Bit rate                                 : 768 kb/s
Channel(s)                               : 6 channels
Channel layout                           : L R C LFE Ls Rs
Sampling rate                            : 48.0 kHz
Frame rate                               : 31.250 FPS (1536 SPF)
Compression mode                         : Lossy
Stream size                              : 333 MiB (5%)
Title                                    : DDP5.1 Atmos
Language                                 : English
Service kind                             : Complete Main
Default                                  : No
Forced                                   : No
Complexity index                         : 16
Number of dynamic objects                : 15
Bed channel count                        : 1 channel
Bed channel configuration                : LFE

Using the app the hungarian track playing via direct playing but the english track is using re-muxing. If I open Jellyfin in the WebOS browser both audio track are direct playing.

Is this normal behavior or a bug?

[dmitrylyzo]

Is this normal behavior or a bug?

In short, it's not always a bug, but it was fixed in 10.9.

In general, on webOS, app uses an older web engine compared to the installed browser. Modern browsers support audio track switching, while older web engines don't.

In your case, LG C9 is webOS 4.x, so in 10.9 it will probably direct play both tracks, since audio track switching is enabled for 4+ (10.8, it is 5+).

On webOS before version 4 it can still behave as you have it now.