Long delay with HTTPS streams

[Fabio Natali]

Dear All,

There seems to be an issue with my Emacs Emms setup when playing HTTPS
radio streams.

tl;dr: It takes a long delay of about 1 minute before an HTTPS stream
starts when played via Emms on my system. HTTP streams are fine,
i.e. they're played almost instantaneously. Both HTTP and HTTPS streams
are fine if played with mpv from the command line.

Find my setup below, together with a brief description of how the
problem can be reproduced on my system.

- mpv 0.33.1
- Emacs 27.2
- GNU/Emms 7.5

My Emms configuration follows, as taken from my init.el:

,----
| (require 'emms-setup)
| (emms-all)
| (emms-default-players)
| (require 'emms-mode-line)
| (emms-mode-line 1)
`----

HTTP and HTTPS streams work fine (i.e. they get loaded and start playing
almost instantaneously) if played with mpv via the command line:

,----
| mpv http://example.com/example-stream
| mpv https://example.com/example-stream
`----

HTTP streams work fine (i.e. they get loaded and start playing almost
instantaneously) via Emms, via `M-x emms-play-url'.

HTTPS streams are where my problem is. If I try to load them via `M-x
emms-play-url', it takes around 1m for them to start playing. The system
is responsive and the Emms mode line would seem to indicate that the
stream is already being played, although it's absolute silence. After
around 1m, the stream finally starts.

I had the chance to ask for help on the `#emacs' IRC channel on
LiberaChat and I was kindly pointed to this quick solution:

,----
| ;; To be added to my init.el
| (setq emms-player-list '(emms-player-mpv))
`----

My `emms-player-list' results otherwise defined as a long list of
alternative players, some of which, AIUI, may get in the way when trying
to play HTTPS streams.

I understand that this may indicate the presence of a little bug
somewhere in the Emms code, so I was suggested to report this here as a
reminder for the Emms developers/maintainers.

Thanks for your help, happy elisp music to All,

Fabio.