unable to extract title

[dirkreinhardt17]

:~/youtube-dl$ ./youtube-dl https://www.youtube.com/playlist?list=PLZA7OK-A5XUv1eTvrNQtLFDwDvj-z45Rw -i -x --audio-format mp3 -v
[debug] System config: []
[debug] User config: []
[debug] Command-line args: ['https://www.youtube.com/playlist?list=PLZA7OK-A5XUv1eTvrNQtLFDwDvj-z45Rw', '-i', '-x', '--audio-format', 'mp3', '-v']
[debug] Encodings: locale UTF-8, fs UTF-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2014.04.04.7
[debug] Python version 2.7.3 - Linux-3.2.0-65-generic-x86_64-with-Ubuntu-12.04-precise
[debug] Proxy map: {}
[youtube:playlist] PLZA7OK-A5XUv1eTvrNQtLFDwDvj-z45Rw: Downloading webpage
ERROR: Unable to extract title; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type youtube-dl -U to update.
Traceback (most recent call last):
File "./youtube-dl/youtube_dl/YoutubeDL.py", line 511, in extract_info
ie_result = ie.extract(url)
File "./youtube-dl/youtube_dl/extractor/common.py", line 161, in extract
return self._real_extract(url)
File "./youtube-dl/youtube_dl/extractor/youtube.py", line 1457, in _real_extract
page, u'title')
File "./youtube-dl/youtube_dl/extractor/common.py", line 380, in _html_search_regex
res = self._search_regex(pattern, string, name, default, fatal, flags)
File "./youtube-dl/youtube_dl/extractor/common.py", line 370, in _search_regex
raise RegexNotFoundError(u'Unable to extract %s' % _name)
RegexNotFoundError: Unable to extract title; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type youtube-dl -U to update.

[phihag]

Make sure you are using the latest version; type ./youtube-dl -U to update.