Checklist

• This is a bug report.
• This is a feature request.
• This is a plugin (improvement) request.
• I have read the contribution guidelines.

Description

I think a great additional feature would be to add an option to only play the audio track from a given stream. This would be a great option for someone who just wants to listen to say, a sports game, but he's on low bandwidth so he doesn't want to waste it on a video stream that he doesn't need. Of course, we can always use the worst option now, but that still requires playing video. Or maybe someone wants to watch a stream in 1080p, but in a different language that's only available with a 480p stream. With audio only, they could play the two side-by-side without wasting the additional resources on playing the video from the lower-quality stream. VLC or ffmpeg always recognizes two distinct streams (audio and video), so that might make it easier to only send the one stream to the player. This could be simply implemented in command line with a parameter like --audio-only.

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