Dolby TrueHD and DTS Master Audio fail to passthrough HDMI
Brief summary of the problem:
AMD 6700 XT video card fails to pass Dolby TrueHD and DTS Master Audio through HDMI to A/V receiver. Other sound formats like Dolby Digital and DTS pass without issue. It works fine on Windows (Same video card). If I use an Nvidia card with exact same hardware and same OS/Kernel it works fine. Pulse Audio is not installed, only ALSA is used for both AMD and Nvidia cards in testing.
Hardware description:
- CPU: AMD Ryzen 5 5600X
- GPU: Gigabyte GV-R67XTGAMING OC-12GD
- System Memory: Corsair CMK64GX4M2D3000C16 32 GB
- Display(s): LG OLEDGX65PUA
- Type of Display Connection: HDMI 2.1
System information:
- Distro name and Version: Ubuntu 20.04.3
- Kernel version: 5.11.0-37-generic
- Custom kernel: None
- AMD package version: 21.30
How to reproduce the issue:
Ensure an HDMI cable goes from AMD video card into an A/V Receiver or A/V Processor that can process DTS-MA or Dolby TrueHD.
< Describe step-by-step how to reproduce the issue >
-
Step 1: Download the ISO of XUbuntu LTS 20.04.03 from a mirror. I live in Canada so I get it from here: http://mirror.csclub.uwaterloo.ca/xubuntu-releases/20.04/release/ Note: I use XUbuntu (XFCE) instead of Gnome for home theater use because it is a lightweight desktop that doesn't have heavy integration with PulseAudio. E.g. if you remove PulseAudio it is clean.
-
Step 2: Then use a utility like "USB Image Writer" on a Ubuntu system (I use my laptop) to create a bootable USB from the ISO.
-
Step 3: Change EUFI/BIOS to boot from the USB key first on HTPC with AMD Card. Boot into the XUbuntu installer in safe graphics mode and install XUbuntu (removing all other OSs).
-
Step 4: After XUbuntu is installed (it comes with kernel 5.11) then proceed to remove PulseAudio
sudo apt remove pulse*
-
Step 5: Then install Radeon Software 21.30 following AMD guide
-
Step 6: Then install latest Kodi:
sudo add-apt-repository ppa:team-xbmc/ppa
sudo apt update
sudo apt install kodi
-
Step 7: Reboot the system. At sign-in screen, select the Kodi session, then sign in after and you should boot right into Kodi (not a XUbuntu session)
-
Step 8: Configure Kodi. Click Yes if asked to enable RTMP input addon. Go to Settings -> System -> Audio -> and change at bottom left to Expert Mode. Set the following settings:
- Audio output device: in my case it sees my A/V receiver connected to HDMI. So I pick HDA ATI, YMH RX-A720 on HDMI 2
- Number of channels: in my case I have more than seven speakers and a Subwoofer (the .1) so I pick the max: 7.1 Scroll down under Audio Passthrough and set the following:
- Allow passthrough - enable
- Passthrough output device - in my case HDA ATI, YMH RX-A720 on HDMI 2
- Dolby digital (AC3) capable receiver - enable
- DTS capable receiver - enable
- TrueHD capable receiver - enable
- DTS-HD capable receiver - enable Note: some of these might not show if your a/v receiver doesn't support them
-
Step 9: Obtain some content to test with from here: There are sample AC-3, DTS, TrueHD and DTS-HD videos from here: https://thedigitaltheater.com/dolby-trailers/ https://thedigitaltheater.com/dts-trailers/
-
Step 10: Play the content through Kodi you downloaded. Go back to Kodi main menu and select Videos. Then go into Files and go find and play the Videos through Kodi. Note, while a video is playing you can press the "O" button to get detailed information on the video and audio being played. When I play DTS or Dolby Digital is shows as that on my receiver and I get the sound coming out the speakers. When I play DTS-HD or Dolby TrueHD is shows as PCM on my receiver and no sound is coming out the speakers (and the video is choppy). When using the Nvidia card it shows proper "Dolby TrueHD" or "DTS-HD".
Attached files:
- Yes compressed collection of many relevant files
- Please take a look at useful.log. It contains dump of HDMI processing when playing a video with Dolby TrueHD.
ALSA information is located at http://alsa-project.org/db/?f=6fee8c33cf6aa49d447ce21bcb2865cb8338e706