Bug: AC3 5.1 audio being transcoded with HDMI passthrough disabled (Nvidia Shield TV Pro)

[kylborn]

Audio is being transcoded instead of direct played with HDMI passthrough disabled.
Audio will direct play with HDMI passthrough enabled.
Audio (supported by all links in the device chain) used to direct play with HDMI passthrough enabled or disabled.

Screenshot of Dashboard (HDMI Passthrough disabled; AC3 being transcoded)

Server Info:
Synology NAS DS416play (DSM 7.0-41890)
Plex Server Version: 1.24.2.4973

Plex Player Info:
NVidia Shield TV Pro (2019)
Shield System Version: 8.2.3
Plex Player Version: 8.23.0.27681 BETA

Server Log:
Plex Media Server Logs_2021-09-04_13-15-57.zip (376.2 KB)

Player Log:
NVidia Shiled PLEX Client Log 202109041315.txt (4.5 MB)

Other notes:
I was still on Synology DSM 6 when I noticed the problem so I updated to DSM 7 but the problem persisted.

On the Shield: I have enabled and disabled “Dolby audio processing” in the advanced sound settings and it does not affect the outcome.

TV Model: Sony XBR-49X700D

Is this a problem between the PLEX client and the Nvidia Shield TV Pro (as the player)?

Having the same issue with same setup but swapping out the TV (TCL instead of Sony).

[sixones]

Thanks for the report, it seems our software decoder wasn’t downloading the AC3 codec, I’ve raised a fix for this and it should land in the next beta.

[kylborn]

Looks like it is working with client version 8.23.0.27740 BETA. Thanks for the quick turnaround and happy Labor Day.

Edit: typo in version number

[TobyX]

@kylborn
I noticed the same issue regarding only DTS audio. Could you replicate this behavior? Unfortunately I’m currently on holidays and cannot test whether it also has been fixed.

[kylborn]

@TobyX
I just ran a quick test and direct play works with both DTS 5.1 and DTS-HD MA 5.1.

I hope that helps.

Edit: I’m currently on PLEX client version 8.23.0.27891 BETA.