Archive.org fails on audio only?

[menachemshapiro]

Trying to download an audio file from archive.org. Got the error message below. I'm not sure if it is because it is an audio only file, or if it is connected to this issue (although the error message is different: #7154

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$ youtube-dl --verbose https://archive.org/details/ybc-fbr-729_4728
[debug] System config: []
[debug] User config: [u'-f', u'18/worst', u'-t', u'-c', u'-i', u'--restrict-filenames']
[debug] Command-line args: [u'--verbose', u'https://archive.org/details/ybc-fbr-729_4728']
[debug] Encodings: locale UTF-8, fs UTF-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2016.08.01
[debug] Python version 2.7.10 - Linux-4.2.0-42-generic-x86_64-with-Ubuntu-15.10-wily
[debug] exe versions: ffmpeg 2.8.3-1, ffprobe 2.8.3-1, rtmpdump 2.4
[debug] Proxy map: {}
[archive.org] ybc-fbr-729_4728: Downloading JSON metadata
ERROR: No video formats 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.
Traceback (most recent call last):
File "/usr/bin/youtube-dl/youtube_dl/YoutubeDL.py", line 682, in extract_info
ie_result = ie.extract(url)
File "/usr/bin/youtube-dl/youtube_dl/extractor/common.py", line 347, in extract
return self._real_extract(url)
File "/usr/bin/youtube-dl/youtube_dl/extractor/archiveorg.py", line 56, in _real_extract
self._sort_formats(formats)
File "/usr/bin/youtube-dl/youtube_dl/extractor/common.py", line 887, in _sort_formats
raise ExtractorError('No video formats found')
ExtractorError: No video formats 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.