--prefer-ffmpeg: command not found

[winterflags]

Make sure you are using the latest version: run youtube-dl --version and ensure your version is 2017.04.03. If it's not read this FAQ entry and update. Issues with outdated version will be rejected.

• I've verified and I assure that I'm running youtube-dl 2017.04.03

Before submitting an issue make sure you have:

• At least skimmed through README and most notably FAQ and BUGS sections
• Searched the bugtracker for similar issues including closed ones

What is the purpose of your issue?

• Bug report (encountered problems with youtube-dl)
• Site support request (request for adding support for a new site)
• Feature request (request for a new functionality)
• Question
• Other

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If the purpose of this issue is a bug report, site support request or you are not completely sure provide the full verbose output as follows:

Add -v flag to your command line you run youtube-dl with, copy the whole output and insert it here. It should look similar to one below (replace it with your log inserted between triple ```):

youtube-dl -f hls-238 https://www.svtplay.se/video/13049986/aktuellt/aktuellt-28-mar-21-00-1?start=auto&tab=senaste --prefer-ffmpeg -v
[1] 57386
-bash: --prefer-ffmpeg: command not found
[SVTPlay] 13049986: Downloading webpage
[SVTPlay] 1377163-050L: Downloading JSON metadata
[SVTPlay] 1377163-050L: Downloading m3u8 information
[SVTPlay] 1377163-050L: Downloading m3u8 information
[SVTPlay] 1377163-050L: Downloading MPD manifest
[SVTPlay] 1377163-050L: Downloading f4m manifest
[download] 100% of 78.63MiB
[ffmpeg] Fixing malformated aac bitstream in "28 mar 21.00 - textat-1377163-050L.mp4"
ERROR: av_interleaved_write_frame(): Invalid argument
<end of log>

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Description of your issue, suggested solution and other information

After updating to 2017.04.03, --prefer-ffmpeg is no longer a recognized command. Note that while the site I'm downloaded from isn't Youtube.com, the very same command I use above has worked in previous months without problem, including --prefer-ffmpeg.

[dstftw]

You have to either put the URL into quotes or manually escape all the special shell characters. Read FAQ entry for details.