Youtube music is not playing

My Mopidy setup is working correctly except playing music from Youtube.

I switched on debugging at it gives the following:

 DEBUG    2016-12-04 13:04:46,600 [4099:HttpServer] mopidy.http.handlers
Received WebSocket message from 192.168.0.153: u'{"method":"core.playback.play","params":{"tl_track":{"track":{"album":{"images":[""],"__model__":"Album","name":"YouTube"},"comment":"0rEsVp5tiDQ","__model__":"Track","name":"Ray Charles - Hit The Road Jack (Original)","uri":"youtube:video/Ray Charles - Hit The Road Jack (Original).0rEsVp5tiDQ","length":140000},"__model__":"TlTrack","tlid":90}},"jsonrpc":"2.0","id":608}'
DEBUG    2016-12-04 13:04:46,677 [4099:HttpServer] mopidy.http.handlers
Sent WebSocket message to 192.168.0.153: '{"jsonrpc": "2.0", "id": 608, "error": {"message": "Application error", "code": 0, "data": {"message": "", "traceback": "Traceback (most recent call last):\\n  File \\"/usr/local/lib/python2.7/dist-packages/mopidy/internal/jsonrpc.py\\", line 133, in _handle_single_request\\n    result = self._unwrap_result(result)\\n  File \\"/usr/local/lib/python2.7/dist-packages/mopidy/internal/jsonrpc.py\\", line 222, in _unwrap_result\\n    result = result.get()\\n  File \\"/usr/local/lib/python2.7/dist-packages/pykka/threading.py\\", line 52, in get\\n    compat.reraise(*self._data[\'exc_info\'])\\n  File \\"/usr/local/lib/python2.7/dist-packages/pykka/compat.py\\", line 12, in reraise\\n    exec(\'raise tp, value, tb\')\\n  File \\"/usr/local/lib/python2.7/dist-packages/pykka/actor.py\\", line 201, in _actor_loop\\n    response = self._handle_receive(message)\\n  File \\"/usr/local/lib/python2.7/dist-packages/pykka/actor.py\\", line 295, in _handle_receive\\n    return callee(*message[\'args\'], **message[\'kwargs\'])\\n  File \\"/usr/local/lib/python2.7/dist-packages/mopidy/core/playback.py\\", line 366, in play\\n    assert tl_track in self.core.tracklist.get_tl_tracks()\\nAssertionError\\n", "type": "AssertionError"}}}'

Any idea?

$ mopidy --version

Mopidy 2.0.1

$ dpkg -l | grep gstreamer1.0
ii  gstreamer1.0-alsa:armhf               1.4.4-2                           armhf        GStreamer plugin for ALSA
ii  gstreamer1.0-libav:armhf              1.4.4-2                           armhf        libav plugin for GStreamer
ii  gstreamer1.0-plugins-bad:armhf        1.4.4-2.1+deb8u1                  armhf        GStreamer plugins from the "bad" set
ii  gstreamer1.0-plugins-base:armhf       1.4.4-2                           armhf        GStreamer plugins from the "base" set
ii  gstreamer1.0-plugins-good:armhf       1.4.4-2+deb8u2                    armhf        GStreamer plugins from the "good" set
ii  gstreamer1.0-plugins-ugly:armhf       1.4.4-2                           armhf        GStreamer plugins from the "ugly" set
ii  gstreamer1.0-tools                    1.4.4-2                           armhf        Tools for use with GStreamer
ii  libgstreamer1.0-0:armhf               1.4.4-2                           armhf        Core GStreamer libraries and elements

If the links become unresponsive, flush the cache like so

sudo python3 -m pip install --force-reinstall --no-cache-dir Mopidy-YTMusic