Rasplex does not pass-through DTS

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1

Hi,

I have my Pi connected in the following order:

Pi -> Receiver (compatible with DTS, DD, AAC, DTS-Ma etc.) -> TV

 

But I can't get the Pi to pass-through the DTS signal it is transcoded to PCM 2.0 each time. This Means that it the receiver sees the same signal no matter if i select the AC3 and DTS pass-through or not.

 

Any one that have experienced simular or have a solution?  

 

I hope that you can help.

2

I am having the same issue as you with a similar setup.  Mine is below:

Pi2 -> Sony Receiver w/ DTS, DD, AAC, etc -> TV

I have checked that the boxes in setup have check marks in them for DTS and AC3 passthrough and I am using HDMI out of my Pi2 and into my receiver and then out to the TV.  Is there a config somewhere I am missing.  I am absolutely loving the response that the Pi2 has and can play any/all of my movies, but only outputs (so far) in 2 channel.

Any ideas?  

3

I can confirm that I have MKV's with DTS audio tracks that passthrough to my AVR without a problem. As per another thread, with less problem than AC3 6ch and 1080P

It is possible unless my receiver is faking the "DTS Decoder" message :-)

What format are your media files in?

4

Hi,
I have my Pi connected in the following order:
Pi -> Receiver (compatible with DTS, DD, AAC, DTS-Ma etc.) -> TV

But I can't get the Pi to pass-through the DTS signal it is transcoded to PCM 2.0 each time. This Means that it the receiver sees the same signal no matter if i select the AC3 and DTS pass-through or not.

Any one that have experienced simular or have a solution?

I hope that you can help.

I'm assuming you have changed the number of channels to be greater than 2.0!

Have you tried swapping the HDMI cable between the Pi and the receiver, some cheap HDMI cables can cause problems, I have Sony receivers and have no problems playing DTS audio on passthrough.

Regards
5

Ned, I did up the channels to 5.1, yes.  The HDMI cable is the same one I unplugged from my Roku XS running Plex that was outputting multi-channel (DTS included).  I as simply just testing the functionality of the RPi2 and noticed the surround not working.  My movies are usually in MKV format with DTS or MP4 w/ AAC 5.1.

The Sony receiver is seeing it come in as LCPM 2.0.  I did find that a command (hdmi_force_edid_audio) may have to be modified as perhaps my reciever is not reporting back that those formats are supported (??).  When i get home this evening I may tinker with that and post back my findings.  Thanks for the help so far!

6

Ned, I did up the channels to 5.1, yes.  The HDMI cable is the same one I unplugged from my Roku XS running Plex that was outputting multi-channel (DTS included).  I as simply just testing the functionality of the RPi2 and noticed the surround not working.  My movies are usually in MKV format with DTS or MP4 w/ AAC 5.1.
 
The Sony receiver is seeing it come in as LCPM 2.0.  I did find that a command (hdmi_force_edid_audio) may have to be modified as perhaps my reciever is not reporting back that those formats are supported (??).  When i get home this evening I may tinker with that and post back my findings.  Thanks for the help so far!


AAC5.1 does indeed passthrough as LPCM2.0, this is fixed in the next release, however DTS (not HD) is passed through as DTS5.1 without any changes to config.txt in 0.5.1 and earlier.

Regards
7

Does it handle AC3 in 5.1 in the same manner as it does DTS?  The config change idea was a shot in the dark ,at best.  Now I am out of ideas as to why it wont get DTS to my receiver then.  Like I said, I simply unplugged the HDMI from the Roku and plugged it into the RPi now I am w/o DTS.  Gotta be something in the RPi me thinks.  As easy as it is to do I may end up reloading it on the microSD card and starting from scratch.   :unsure:

8

Does it handle AC3 in 5.1 in the same manner as it does DTS?  The config change idea was a shot in the dark ,at best.  Now I am out of ideas as to why it wont get DTS to my receiver then.  Like I said, I simply unplugged the HDMI from the Roku and plugged it into the RPi now I am w/o DTS.  Gotta be something in the RPi me thinks.  As easy as it is to do I may end up reloading it on the microSD card and starting from scratch.   :unsure:

Well, no luck there either. In fact, opening up some movies I hadn't before showed me that it wont even output AC3 in 5.1 either. I really love the speed this thing offers, but not having ANY surround sound is a deal killer.  Might try randomly swapping out HDMI cables and hope I don't have to turn this thing into a door stop.  

9

Anyone have any ideas?  I have tried 3 different HDMI cables, 2 total rebuilds from scratch and 2 different HDMI ports on my receiver (Sony STR-DH710).  Does my Roku XS not pass through DTS the same way my RPi2 should?  I ask because the Roku works great for audio, but cannot handle the higher bit rate video stuff w/o down-coding it.  The RPi2 handles ALL my videos like a boss, but only outputs in LCPM 2.0 format.  

I have half a mind to run the RPi2 straight to the TV and audio back down to the receiver, but I've read that a lot of TVs cannot pass DTS or DD back down (true??).   I can't give up on this little thing as there is so much it does right.  Help.

10

Here’s a silly question but when you are in the preplay screen, did you select the audio track icon under play and specifically select the DTS track?

11

Here's a silly question but when you are in the preplay screen, did you select the audio track icon under play and specifically select the DTS track?

Good question rcork, but yes, it is checked everytime I try to play a file. 

12

What is the output from running the following command on the Raspberry Pi:

tvservice -a
13

What is the output from running the following command on the Raspberry Pi:

tvservice -a

I am very much a beginner at this so here is what I tried, and failed, to do that.  I downloaded Putty, ssh'd into the RPi2 and ran the cmd you gave me.  The return in the Putty window says "[E] Failed to initialize VCHI (ret=-1)

14

I am very much a beginner at this so here is what I tried, and failed, to do that.  I downloaded Putty, ssh'd into the RPi2 and ran the cmd you gave me.  The return in the Putty window says "[E] Failed to initialize VCHI (ret=-1)

What is in your config.txt? If you don't know how to view that file, execute this commands from the Pi and post the result

cat /flash/config.txt
15
rcork, it is posted below, straight stock, from the flash.
 
################################################################################
#      This file is part of OpenELEC - http://www.openelec.tv
#      Copyright (C) 2009-2012 Stephan Raue (stephan@openelec.tv)
#      Inspired and partly copied from:
#  http://youresuchageek.blogspot.fr/2012/09/howto-raspberry-pi-openelec-on.html
#
#  This Program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2, or (at your option)
#  any later version.
#
#  This Program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with OpenELEC.tv; see the file COPYING.  If not, write to
#  the Free Software Foundation, 51 Franklin Street, Suite 500, Boston, MA 02110, USA.
#  http://www.gnu.org/copyleft/gpl.html
################################################################################
# Bootloader configuration - config.txt
################################################################################
 
################################################################################
# Memory (System/GPU configuration )
################################################################################
 
# default GPU memory split (do not change if you do not know what you are doing)
  gpu_mem=128
 
# SDRAM size based GPU memory split, uncomment and setup to override 'gpu_mem'
  gpu_mem_256=54
  gpu_mem_512=128
 
################################################################################
# Overclocking settings
# WARNING: Do not change/enable if you do not know what you are doing!
#          The System may become unstable or you can have data corruption or
#          you can loose your warranty if you set wrong settings
#
# please read: http://elinux.org/RPi_config.txt#Overclocking_configuration
################################################################################
 
# Overclock mode settings.
#
# default recommended values are: arm_freq | core_freq | sdram_freq | over_voltage
# no overclocking               :    700   |    250    |    400     |      0
# mode 'Modest'                 :    800   |    300    |    400     |      0
# mode 'Medium'                 :    900   |    333    |    450     |      2
# mode 'High'                   :    950   |    450    |    450     |      6
# mode 'Turbo'                  :   1000   |    500    |    500     |      6
 
# arm_freq=700
# core_freq=250
# sdram_freq=400
# over_voltage=0
 
# set to 'force_turbo=1' to disable dynamic overclocking (you can lose your warranty!)
  force_turbo=0
 
# If you have any data corruption using Turbo Mode and overclocking
# try with this setting uncommented
# If this still fails, try to use Medium mode without "over_voltage=2"
# If it ultimately keeps failing, forget about this until it gets fixed
# Use a more conservative mode that will works fine in any cases:
# initial_turbo=30
 
################################################################################
# Overscan settings
################################################################################
 
# Make display smaller to stop text spilling off the screen
# see also http://www.raspberrypi.org/phpBB3/viewtopic.php?f=67&t=15700
# overscan_scale=1
# disable_overscan=1
 
# Adapt overscan values to your needs
# overscan_left=57
# overscan_right=59
# overscan_top=20
# overscan_bottom=20
 
################################################################################
# various settings see also: http://elinux.org/RPi_config.txt
################################################################################
 
# Force HDMI even if unplugged or powered off
# hdmi_force_hotplug=1
 
################################################################################
# License keys to enable GPU hardware decoding for various codecs
# to obtain keys visit the shop at http://www.raspberrypi.com
################################################################################
 
# decode_MPG2=0x00000000
# decode_WVC1=0x00000000
# decode_DTS=0x00000000
# decode_DDP=0x00000000
 
################################################################################
#
# >>>>>>>> RasPlex default settings override <<<<<<<<<
#
################################################################################
 
hdmi_force_hotplug=1
hdmi_drive=2
gpu_mem_256=64
gpu_mem_512=200
dtoverlay=lirc-rpi
 
 
################################################################################
# End of default configuration
# all values below this line were inserted from config.txt.bk (your old config)
# and can be merged with the above values
################################################################################
16

Ok, let's try to set a few settings and see if they help. It's probably easiest to shutdown the Pi, take the SD card out and plug it into your computer and edit the config.txt file from there. Assuming your TV is a 1080p set, add the following lines to your config.txt

hdmi_ignore_edid=0xa5000080
hdmi_force_edid_audio=1
hdmi_group=1
hdmi_mode=16

Also, i think you said you have a Raspberry Pi 2 so change the gpu memory to 256

gpu_mem=256

Also comment out the gpu_mem_256 and 512 options for now (in 2 places in your config.txt). Since the RPi2 has 1GB of RAM, i don't think those two options are used but lets be safe

# gpu_mem_256=64
# gpu_mem_512=200

After saving the file, put the SD card back in the RPi2, boot up, log in via SSH, run the tvservice -a command again and see if this time you don't get an error. If not, post the output.

17

So, this is now what the bottom of my config.txt file looks like, hope it's right:

################################################################################
#
# >>>>>>>> RasPlex default settings override <<<<<<<<<
#
################################################################################
 
hdmi_force_hotplug=1
hdmi_drive=2
#gpu_mem_256=64
#gpu_mem_512=200
dtoverlay=lirc-rpi
 
hdmi_ignore_edid=0xa5000080
hdmi_force_edid_audio=1
hdmi_group=1
hdmi_mode=16
gpu_mem=256
 
################################################################################
# End of default configuration
# all values below this line were inserted from config.txt.bk (your old config)
# and can be merged with the above values
################################################################################
18

loaded it up, booted it, ran the tvservice -a command and got the same error.

19

Out of ideas on why tvservice isn’t working. Try playing DTS content and see if it works

20

All audio still LCPM.