Merge remote-tracking branch 'jaimeMF/opus-fix'

diff --combined youtube_dl/PostProcessor.py
index 0479591f00c49fb1a4e2205c7cf4dc805ee04122,07b6895c0abb5c424edf6345cefae1c08d97f088..039e014982e2396ad3175a4c3fcd3dc15030952e
--- 1/youtube_dl/PostProcessor.py
--- 2/youtube_dl/PostProcessor.py
+++ b/youtube_dl/PostProcessor.py
@@@ -83,8 -83,6 +83,8 @@@ class FFmpegPostProcessor(PostProcessor
                 + opts +
                 [encodeFilename(self._ffmpeg_filename_argument(out_path))])
  
 +        if self._downloader.params.get('verbose', False):
 +            self._downloader.to_screen(u'[debug] ffmpeg command line: %s' % shell_quote(cmd))
          p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
          stdout,stderr = p.communicate()
          if p.returncode != 0:
@@@ -180,7 -178,8 +180,8 @@@ class FFmpegExtractAudioPP(FFmpegPostPr
              extension = self._preferredcodec
              more_opts = []
              if self._preferredquality is not None:
-                 if int(self._preferredquality) < 10:
+                 # The opus codec doesn't support the -aq option
+                 if int(self._preferredquality) < 10 and extension != 'opus':
                      more_opts += [self._exes['avconv'] and '-q:a' or '-aq', self._preferredquality]
                  else:
                      more_opts += [self._exes['avconv'] and '-b:a' or '-ab', self._preferredquality + 'k']