Pipewire no sound over HDMI

This is the second time that i was bitten by the same thing. One a few years ago and another a few days while setting my new pc. I have spent around two hours ending on the same post both times. So here its for future me to not lose it.

I have installed Pipewire and everything was working. I connected my tv over HDMI to play some movies but sound wasnt coming.

It was interesting, because seing pavucontrol-qt sound was recognised. Heck, even aplay -l recognized the output. Doing some tests with speaker-test --channels 2 --test wav --device hw:0,3 and it played. So it must be some kind of configuration with pipewire.

To my luck, thanks to this post by Ignacio Brittez i found out that my tv cant play 32bit audio, so i have to reduce it to 16bits.

First of all copy the default config

cp -r /usr/share/wireplumber ~/.config/

Then edit ~/.config/wireplumber/wireplumber.conf.d/alsa-vm.conf with the following content

# ALSA node property overrides for HDMI output
monitor.alsa.rules = [
  {
    matches = [
      { node.name = "~alsa_output.*" }
    ]
    actions = {
      update-props = {
        audio.format = "S16LE"
        audio.channels = 2
        audio.position = "FR,FL"
      }
    }
  }
]

The important thing here is the audio.format = “S16LE” part. And now i can enjoy my movies in its full low quality sound.