Server Version#: 1.25.2.5319 (QNAP NAS TVS-472XT)
Player Version#: 8.28.30077 (Amazon FireTV 4K Max)
Hi all, I am struggling to fine-tune my Plex setup on my FireTV stick
My setup:
FireTV Stick 4K Max > HDMI Audio Extractor box > TV
HDMI Audio Extractor > Optical TOS > Logitech Dolby Digital 5.1 (Z906)
I have a library with most of the videos having multiple tracks (Russian and original)
Formats vary, AC3, AAC, DTS are most common.
Audio Receiver (Logitech Z906) does not support DTS and higher, so it handles AC3 and E-AC3 only.
Before going to FireTV I was using Dune Media player (HW) and it was playing everything with best sound option available and was transcoding non-supported audio to AC3 so my audio could handle it.
With new setup I have to utilize Audio-Passthrough option while without it, Plex is downmixing the audio to PCM Stereo and I am lacking multi-channel playback with passthrough disabled.
I have tried both HDMI Passthrough and Optical Passthrough and here are my findings and issues:
- HDMI passthrough
Issue 1: There are no additional settings available and passthrough works fine for AC3 tracks but DTS tracks are downmixed to stereo. There is no way to control this and to force DTS>AC3 transcoding for passthrough
Issue 2: Tracks got mixed. I.e. when I select Track 1, Track 2 is played instead. When I select Track2, Track 1 is played instead
- Optical passthrough
In this setup I can select AC3 and deselect DTS in the options. This makes DTS tracks playback in multichannel working! BUT:
Issue : With direct play mode (no transcoding) - tracks got mixed as described above, but it’s more weird, I am typically not able to play first Audio track at ALL. (unless there is only 1 track).
So in example:
Track 1: AC3 5.1, Russian
Track 2: DTS 5.1, English
selecting track 1: track 2 is played in downmix stereo (no 5.1)
selecting track 2: track 2 is played in 5.1 mode
Workaround is to FORCE A/V transcoding (conversion) in the Player.
If I switch from Direct play to Convert automatically during playback, all issues are resolved, tracks are playing as they are supposed to play, no mix and also 5.1 everywhere where it is available (AC3, AAC, DTS, DTS-HD)
It is not possible to keep forced conversion, but as per below article, there is a workaround
https://support.plex.tv/articles/115007570148-automatically-adjust-quality-when-streaming/
- set Adjust Quality Automatically to ON
- set default playback quality in Home streaming to a low setting, i.e 4 Mbps (720P) to force transcoding to be turned ON during playback. After a minute quality is increased automatically to max, but transcoding is kept enabled and audio streams are working fine.
QUESTION:
1. Is there any way to troubleshoot/fix the incorrect audio tracks playback with Audio Passthrough enabled and when using ‘Direct play’?
2. When HDMI passthrough is used - any chance to add DTS+ transcoding options to ‘lower’ AC3 in case if receiver does not support it (instead of downmixing to stereo)? I have been using VIMU player (also based on Exoplayer) and it does support this transcoding in settings.
some similar issues were discussed here:
