'tizonia --youtube-audio-mix-search' fails with 'TypeError: sequence item 9: expected string or Unicode, dict found'

[juanrubio]

$ tizonia --youtube-audio-mix-search "Michael Jackson"
tizonia 0.9.0. Copyright (C) 2017 Juan A. Rubio
This software is part of the Tizonia project <http://tizonia.org>

[2017-10-13 20:58:03,156] [ INFO] [140241618732800] 
[YouTube] (TypeError) : sequence item 9: expected string or Unicode, dict found
Traceback (most recent call last):
  File "/home/joni/temp/lib/python2.7/site-packages/tizyoutubeproxy.py", line 461, in enqueue_audio_mix_search
    for track_info in get_tracks_from_json(wdata2):
  File "/home/joni/temp/lib/python2.7/site-packages/tizyoutubeproxy.py", line 201, in get_tracks_from_json
    'id': ','.join([get_track_id_from_json(i) for i in items])}
TypeError: sequence item 9: expected string or Unicode, dict found