No audio on thin client pc with HA OS

I’ve installed Home Assistant OS on thin client PC (HP t620). Radio browser is installed on my dashboard and streaming audio from a radio channel to my laptop is working OK. However I want to stream the radio channel to my stereo amplifier. Therefore I have connected the line out of the sound card of the t620 to my stereo amplifier.
However, there is no audio signal on the t620 line-out soundcard. Also the t620 headphone plug doesn’t work.
Does anybody have an idea how to get the audio on my stereo amplifier?

Install VLC player or Mopidy.
That will give you an option in their config to select Audio_out of the PC where HAOS runs on

How can I install Mopidy? It is not available in the add-ons …
i did install VLC, but at configuration I only can make a choice for:
output: built-in audio analog stereo
But this does not result in sound at the HP t620

Mopidy might be available through hacs, install instructions here

I managed to get HACS integrated in Home Assistant.
But for me not clear how to get Mopidy out of HACS into Home assistant?

You’d have to find the install instructions for mopidy to follow.

Here they are, and yes, it’s installed through hacs. You may need to add a custom repository as a source but it’ll all be explained in the in instructions, I’m sure.

Sorry, for me its completely new stuff. So I’ve probably some stupid questions!

I’ve installed Mopidy, and it is available in HA dashboard
However I’ve difficulty in filling in the right info at setup:

-media_player:
name: arbitrary name, e.g. Mediaplayer ?
host: IP address of my PC where HA is installed (HPt620) ?
port: port if different from 6680 which port should I choose?

For mopidy i have this in my configuration.yaml

media_player:
# https://github.com/bushvin/hass-integrations
- name: 'mopidy_player'
  host: '192.168.1.84' #<FQDN or IP address>
  #port: <port if different from 6680>
  platform: mopidy

Besides build in audio i have also connected a cheap USB audio device and i have selected that one in the configuration of mopidy.
Under Supervisor - Hardware the USB device shows up as detected

About VLC
I have installed “VLC media player via Telnet” under devices
and under Add-On i have installed VLC v0.3.0
VLC player is in the configuration connected with the [Buildin audio analog stereo]
This device must be available and active on the motherboard of the hostPC where HAOS runs to be detected.

I have with both methodes audio output on my HAOS PC which is a small NUC

Trying to install VLC-via Telnet, I get the problem of a non secure connection.
Screenshot from 2024-10-30 19-36-32
Is your filled in IP address your HAOS PC IP address or is it from a VPN connection?

If I remember well this is an auto discovery addon. At least I can’t find any configuration to set a password
Please have a look at this link where they seem to have the same trouble
https://github.com/home-assistant/addons/issues/3186#issuecomment-1686095909

Basically it says remove everything VLC related and add ono by one in the right order.