超初心者です。kivyのsoundloaderでエラーになってしまうことに関して

kivyのsoundloaderでエラーになってしまうことに関してです。
以下のコードを入れると、

Python
1from kivy.core.audio import SoundLoader
2sound = SoundLoader.load('/Users/~/Desktop/Clock-Alarm05-1.mp3')
3if sound:
4    print("Sound found at %s" % sound.source)
5    print("Sound is %.3f seconds" % sound.length)
6    sound.play()
7

以下のエラーがでます。

Python
1(process:5460): GLib-GObject-WARNING **: 16:51:54.499: gsignal.c:2523: signal 'sync-message' is invalid for instance '0x7fb5b28b9940' of type '(null)'
2 Traceback (most recent call last):
3   File "sad.py", line 2, in <module>
4     sound = SoundLoader.load('/Users/~/Desktop/Clock-Alarm05-1.mp3')
5   File "/Users/~/opt/anaconda3/lib/python3.7/site-packages/kivy/core/audio/__init__.py", line 85, in load
6     return classobj(source=filename)
7   File "/Users/~/opt/anaconda3/lib/python3.7/site-packages/kivy/core/audio/audio_gstplayer.py", line 45, in __init__
8     super(SoundGstplayer, self).__init__(**kwargs)
9   File "kivy/_event.pyx", line 264, in kivy._event.EventDispatcher.__init__
10   File "kivy/properties.pyx", line 497, in kivy.properties.Property.__set__
11   File "kivy/properties.pyx", line 544, in kivy.properties.Property.set
12   File "kivy/properties.pyx", line 599, in kivy.properties.Property.dispatch
13   File "kivy/_event.pyx", line 1248, in kivy._event.EventObservers.dispatch
14   File "kivy/_event.pyx", line 1154, in kivy._event.EventObservers._dispatch
15   File "/Users/daigomasatsugu/opt/anaconda3/lib/python3.7/site-packages/kivy/core/audio/__init__.py", line 175, in on_source
16     self.load()
17   File "/Users/~/opt/anaconda3/lib/python3.7/site-packages/kivy/core/audio/audio_gstplayer.py", line 62, in load
18     self.player.load()
19   File "kivy/lib/gstplayer/_gstplayer.pyx", line 233, in kivy.lib.gstplayer._gstplayer.GstPlayer.load
20 kivy.lib.gstplayer._gstplayer.GstPlayerException: Unable to create a playbin. Consider setting the environment variable GST_REGISTRY to a user accesible path, such as ~/registry.bin
21 
22