when i put the previous bottom for change song crash

[antonio]

when i put the previous bottom for change song crash the covergloobus the name of theme is RUN

here is the details:

Traceback (most recent call last):
  File "/usr/share/covergloobus/core/ui.py", line 336, in <lambda>
    button.connect('clicked', lambda w: self.cg.player.previous())
  File "/usr/share/covergloobus/players/generic/Mpris2.py", line 177, in previous
    self._player.Previous()
  File "/usr/lib/python2.7/dist-packages/dbus/proxies.py", line 145, in __call__
    **keywords)
  File "/usr/lib/python2.7/dist-packages/dbus/connection.py", line 651, in call_blocking
    message, timeout)
DBusException: org.gtk.GDBus.UnmappedGError.Quark._rb_5fshell_5fplayer_5ferror.Code1: No previous song