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Psyduckap · 2015-02-19, 10:46

Hi.

I can't get ac3 passthrough with dvdplayer. With omxplayer the same files do passthrough.
I've tried with mkvs, BD Isos, and dvds. All work ok with omxplayer but with dvdplayer I only get noise. Other audio tracks in the files work well with dvdplayer. If I disable passthrough, ac3 tracks play well.

My setup:
Raspberry pi B with Openelec 5.0.3 -> HDMI -> TV -> Optical -> Amplifier
Number of channels: 2
Changed Raspberry B with Raspberry 2 and it's the same
I think with Openelec 4.x was the same, at least with dvds

tvservice -a output:
PCM supported: Max channels: 2, Max samplerate: 48Khz, Max samplesize 24 bits
AC3 supported: Max channels: 6, Max samplerate: 48Khz, Max rate 640 kb/s

What else have to configure to get ac3 passthrough with dvdplayer?

Regards

dkscan · 2015-02-20, 10:02

I have the exact same problem.

I was hoping that the Pi2 could transcode DTS into AC3 as my Sonos Playbar does not support DTS. However this does not seem to work and even worse dvdplayer does not play AC3 at all when passthrough is enabled.

My setup:
Raspberry Pi 2 with OSMC -> HDMI -> TV -> Optical -> Sonos Playbar

Settings:
Audio Output Device = HDMI
Number of channels = 2.0
Output configuration = Optimized
Resample quality = GPU accelerated
Keep audio devices alive = 1 Minute
Play GUI sounds = Never
Enable passthrough =On
Passthrough output device = HDMI
Dolby Digital (AC3) capable receiver = On
Enable Dolby Digital transcoding = On
Dolby Digital Plus (E-AC3) capable receiver= Off
DTS capable receiver = Off

Using dvdplayer only stereo soundtracks is played ok. AC3 and DTS results in noise only. If I turn passthrough off AC3 and DTS is correctly downmixed and output as stereo.

Using OMXplayer AC3 is passed through as expected. DTS gets downmixed to stereo which is as expected as I understand that OMXPlayer is not expected to support transcoding.

I have a lot of DVD iso-files which I would like to play with dvdplayer as it supports DVD menus but not being able to get surround sound is a major drawback. For the moment I play those DVD's on my old PopCorn Hour A-110 but was hoping to completely replace it with Raspberry Pi2.

I have also tested with an old Raspberry Pi and another tv without soundbar. Results are the same as above.

Psyduckap · 2015-02-22, 14:15

Which brand are your tv and amp?
My tv is Sony and my amp is denon.
Maybe something to do with brands.

dkscan · 2015-02-22, 15:02

My tv is a Sony 55X8505B and the amp is a Sonos Playbar.
The other tv without soundbar I tested with was a Sony KDL-40W4500.

Newer Sony's typically supports passing DD5.1 from HMDI input to optical out.

Since we get noise dvdplayer must be putting something out but clearly not AC3 as expected.

Psyduckap · 2015-02-22, 18:07

Mine is a 40W905.

Maybe Sony tvs dont understand what dvdplayer puts in.

Here http://forum.kodi.tv/showthread.php?tid=218309 dvdplayer transcodes to ac3 and do passthrough to a tv and from there to an amp.

I'm going to ask him his tv brand.

dkscan · 2015-02-22, 19:19

Yes could be interesting to know what he is using. Looks like he got transcoding from DTS to AC3 to work by disabling OMXPlayer. If I do that only stereo tracks will play when passthrough is enabled.

Lightgr · 2015-03-10, 11:35

Hello

I have the exact same issue. Omxplayer can passthrough ac3 just fine, and downmix dts to 2 channels, but with dvdplayer i hear nothing but static when pass through is enabled.
This happens with ac3 audio tracks or transcoded dts and static is heard on both tv/amp. Without pass through dvdplayer plays fine as well.

My setup is
openelec 5.0.5 (also tried some milhouse's builds, same result)
Settings same as dkscan's

Rpi2 ---> Sharp Aquos LC-50LE750 -----> Sony str840db Amp ( tv has spdif coaxial out and supports only Ac3 for passthrough)

Here is a weird thing i noticed though. With dvdplayer and trying to passthrough ac3 files it starts the noise but after 4-5 seconds amp shows a signal of DTS 1.0 (static continues though) !

Regards

**popcornmix** · 2015-03-10, 13:38

(2015-03-10, 11:35)Lightgr Wrote: Here is a weird thing i noticed though. With dvdplayer and trying to passthrough ac3 files it starts the noise but after 4-5 seconds amp shows a signal of DTS 1.0 (static continues though) !

Does power cycling the receiver when audio is playing do anything?

Lightgr · 2015-03-10, 17:33

(2015-03-10, 13:38)popcornmix Wrote: Does power cycling the receiver when audio is playing do anything?

When i try that the receiver stays without signal and after 10+ secs it locks the signal as dts 1.0 (center channel only). In that scenario there is no audible sound from the receiver ( no noise). The tv continues to produce noise.

I think the problem lies in the way that dvdplayer flags/route(?) the audio stream. If it was only in the transcoding part (like when doing dts--->ac3) it could have been an encoding incompatibility. But as the problem also occurs with native ac3 tracks it makes me think that somehow it is altered as it gets output. (As i have read Omx bitstreams it directly and dvdplayer doesnt hence the ability to transcode)

PS. I also tried with the hdmi_force_edid_audio=1 option and the result is the same. And with osmc as well (noise)

Regards

Psyduckap · 2015-03-11, 12:40

(2015-03-10, 13:38)popcornmix Wrote: Does power cycling the receiver when audio is playing do anything?

I've tried it and still noise (mine doesn't show Dolby Digital at all, not before not after)

amandus99 · 2015-03-16, 23:04

I got the same issue, only noise when using ac3 passthrough

Pi -> TV -> Denon

cable settop box, ASUS Hdpr1, PS3 are working fine with ac3 passthrough, so the TV shouldn't be the issue.

amandus99 · (This post was last modified: 2015-03-20, 08:23 by amandus99.)

Would it help to buy a shield with optical out to go directly to the avr?

cabracabra · 2015-04-01, 11:20

(2015-03-16, 23:04)amandus99 Wrote: I got the same issue, only noise when using ac3 passthrough

Pi -> TV -> Denon

cable settop box, ASUS Hdpr1, PS3 are working fine with ac3 passthrough, so the TV shouldn't be the issue.

Same here with similar setup Pi2-->Tv Sony-->Ampli Denon (1802)

The problem is Dvdplayer that seems not work correctly with passthrough and play only noise, disabling Dvdplayer audio is ok but some dvds not play correctly.

In my case I have also a problem with Dts audio, I'm not able to reproduction any Dts audio tracks, instead of noise I don't hear anything.

Lightgr · (This post was last modified: 2016-02-20, 02:49 by Lightgr.)

I am happy to report that our problem is (most probably) fixed !

As per http://openelec.tv/forum/134-usage/79850...ade#158003 , replacing the 2 files that popcornmix provided i can report that passthrough now works with only mmal enabled! (Omx had no problems)

Ac3 and all of the transcodings that i tried (DTS, AAC 5.1 and flac 5.1 ) produce sound without problems (nice ac3 5.1) !

As i stated before, i have Raspi------>Sharp Aquos Tv------>Sony 5.1 receiver (spdif).

I am pretty sure that now it works on other televisions too.

Thank you Popcornmix !!!

Regards

Edit: These files were tested on Openelec 6.0.1 . I dont know if they are compatible with other Openelec versions. Also the fix is integrated in the latest Milhouse build http://forum.kodi.tv/showthread.php?tid=...pid2251289