[Icecast] error from relay request

[Christophe PEREZ]

Hi,

On my own icecast server (2.4.4 on gentoo), I want to relay 
http://audio.bfmtv.com/rmcradio_128.mp3

I can play it with mpv.
My config for this relay :
    <relay>
        <server>audio.bfmtv.com</server>
        <port>80</port>
        <mount>/rmcradio_128.mp3</mount>
        <local-mount>/rmc.mp3</local-mount>
        <relay-shoutcast-metadata>1</relay-shoutcast-metadata>
        <on-demand>1</on-demand>
    </relay>

(I have about 10 relays working fine for years)

But, I can't get it working.

If I try to play it with :
$ mpv http://myicecastserver:8000/rmc.mp3
[ffmpeg] http: HTTP error 404 File Not Found
Failed to open http://stream.novazur.fr:8000/rmc.mp3.
[ytdl_hook] ERROR: Unable to download webpage: HTTP Error 404: File Not
Found (caused by <HTTPError 404: 'File Not Found'>); please report this
issue on https://yt-dl.org/bug . Make sure you are using the latest
version; type  youtube-dl -U  to update. Be sure to call youtube-dl
with the --verbose flag and include its complete output. 
[ytdl_hook] youtube-dl failed: unexpected error occurred 

And icecast logs give :
[2021-07-03  14:20:03] EROR slave/open_relay_connection Error from
relay request: /rmc.mp3 (Bad Request)
[2021-07-03  14:20:05] EROR connection/_handle_connection Wrong request
type from client

But why can't I relay this one ?

Thanks
And sorry about my poor english.

-- 
Christophe PEREZ