[S905X4] HDMI Audio on HTV H8 (Kernel 6.18) - GPU working, but no Sound

[pedrohrigolin]

Hi @devmfc, thanks for the great work on these images.

I successfully booted your Debian Image (Kernel 6.18.5) on an HTV H8 TV Box (Amlogic S905X4) using the ah212-generic DTB.

I managed to get GNOME running on Wayland and it works flawlessly with Panfrost GPU acceleration active (Mali G31). The system is very smooth and stable.

However, I have no HDMI Audio. The system does not detect the sound card (aplay -l shows no cards found).

I know SC2 (S905X4) audio support in mainline is tricky, but since the video is working so well, I was wondering if there is any workaround? Are there specific modules I should try to load, or is the audio driver for this SoC currently completely missing from the 6.18 build?

Thanks for any help!

[projetotvbox]

@devmfc We really need your help to solve this issue.

[araczkowski]

I managed to get GNOME running on Wayland and it works flawlessly with Panfrost GPU acceleration active (Mali G31). The system is very smooth and stable.
@pedrohrigolin can you share/describe how you did this? Thanks

[pedrohrigolin]

Hi! Sure, here's a breakdown of what was done:

My approach — Custom Armbian build with kernel swap:

I compiled an Armbian image targeting the BananaPi M2 Pro (Amlogic S905X3), which was the closest supported board profile to my TV Box (Amlogic S905X4). After that, I replaced the original Armbian kernel with @devmfc's kernel, properly placing all modules and DTBs. Some DTB adjustments were also made to better match my specific TV Box hardware. Since I had already compiled Armbian with GNOME + Wayland included, it booted straight into the desktop.

---

Alternative approach — done by my professor, starting directly from @devmfc's image:

After flashing the image, GNOME + Wayland was installed manually:

# Check DRM/KMS is active
ls /dev/dri
# Expected: card0, card1, renderD128

apt install mesa-utils libdrm-dev libegl1 libgles2
apt install libwayland-dev wayland-protocols xwayland
apt install gnome-shell gdm3 gnome-session gnome-menus gnome-control-center \
    gnome-terminal gnome-system-monitor gnome-text-editor nautilus
apt install gnome-shell-extensions gnome-tweaks gnome-shell-extension-manager \
    gnome-shell-extension-appindicator
apt install xdg-utils xdg-user-dirs-gtk gir1.2-gnomedesktop-3.0

# Enable GDM and set graphical boot target
sudo systemctl enable gdm
sudo systemctl set-default graphical.target
sudo reboot

Optionally, to get a more Windows-like desktop feel:

sudo apt install arc-theme papirus-icon-theme
gnome-extensions enable user-theme@gnome-shell-extensions.gcampax.github.com
gsettings set org.gnome.desktop.wm.preferences button-layout ':minimize,maximize,close'
# Then install "Dash to Panel" and "Desktop Icons NG (DING)" via Extension Manager

---

Regarding HDMI audio: Neither approach produced working audio via HDMI or SPDIF. As you noted, SC2/S905X4 audio support in mainline is still a known gap — video and GPU (Panfrost/Mali G31) worked flawlessly, but no sound card is detected (aplay -l returns empty).

Proper documentation will be available soon at: https://github.com/projetotvbox

[araczkowski]

Hi! Thanks for the detailed breakdown.

Great news — it seems your method works on my box too! I'm testing it on an S905X3 and, unlike the X4, HDMI audio is working perfectly here, along with Bluetooth audio. Since you're struggling with the X4 mainline gap, maybe try checking if Bluetooth audio works for you as a temporary workaround? It often bypasses the HDMI/ALSA routing issues.

Regarding the installation process: your manual approach is very clean. I think adding an installation script to the release is a fantastic idea. It would really lower the barrier for others.
@devmfc let me know if you want me to help draft that script or test it on the S905X3 side.

[araczkowski]

the full installation script :)

#!/bin/bash

# Default username variable
DISTR="box"

# 1. Check if the script is running as root
if [ "$EUID" -ne 0 ]; then
  echo "ERROR: This script must be run as root (use sudo or log in as root)."
  exit 1
fi

echo "--- Starting GNOME + Wayland Installation ---"

# 2. Update package lists
apt update

# 3. Install packages (using -y to automatically accept prompts)
# Using DEBIAN_FRONTEND=noninteractive to skip prompts for GDM3 configuration
echo "--- Installing graphics libraries and Wayland ---"
DEBIAN_FRONTEND=noninteractive apt install -y mesa-utils libdrm-dev libegl1 libgles2 sudo
DEBIAN_FRONTEND=noninteractive apt install -y libwayland-dev wayland-protocols xwayland

echo "--- Installing GNOME Core ---"
DEBIAN_FRONTEND=noninteractive apt install -y gnome-shell gdm3 gnome-session gnome-menus gnome-control-center \
    gnome-terminal gnome-system-monitor gnome-text-editor nautilus

echo "--- Installing Extensions and Tools ---"
DEBIAN_FRONTEND=noninteractive apt install -y gnome-shell-extensions gnome-tweaks gnome-shell-extension-manager \
    gnome-shell-extension-appindicator xdg-utils xdg-user-dirs-gtk gir1.2-gnomedesktop-3.0

# 4. System configuration
echo "--- Configuring GDM and graphical target ---"
systemctl enable gdm
systemctl set-default graphical.target

# 5. Fix for root account (allows logging in to GUI as root)
if [ -f /etc/pam.d/gdm-password ]; then
    sed -i 's/.*pam_succeed_if.so user != root.*/#&/' /etc/pam.d/gdm-password
    echo "PAM fix applied for root account."
fi

# 6. Interactive creation of a new user
echo "------------------------------------------------"
echo "--- CREATING NEW USER FOR DESKTOP ENVIRONMENT ---"
echo "------------------------------------------------"

# Get username
echo -en "Please enter new username for desktop environment [${DISTR}]: "
read USER_NAME
USER_NAME=${USER_NAME:-${DISTR}}

# Get password (hidden input)
echo -en "Please enter password for ${USER_NAME}: "
read -s USER_PASSWORD
echo "" # New line after hidden password

# Create user
adduser --quiet --disabled-password -gecos "${USER_NAME}" "${USER_NAME}"

# Set password
echo "${USER_NAME}:${USER_PASSWORD}" | chpasswd

# Add user to sudo group (to allow system management)
usermod -aG sudo "${USER_NAME}"

echo "--- Done! User ${USER_NAME} has been created and added to the sudo group. ---"
echo "Script finished. You can now type: reboot"

[pedrohrigolin]

Thanks for the feedback and for testing it on your side — really appreciate it.

I also managed to get Bluetooth audio working on my box, and USB audio works as well. However, since I'm part of a project focused on repurposing TV boxes that will be redirected to underserved communities by the Brazilian Federal Revenue Service, having HDMI and SPDIF audio working would be very important for our use case.

From what we've investigated so far, it seems to be related to missing hardware support. Developing a proper driver for this is one of the goals that I and the @projetotvbox team are looking into, but there’s no timeline yet.

For now, we’ll keep working with Bluetooth and USB audio as temporary solutions.