"Remove spikes" at start, error

spikesbug2.py

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
/Users/thomas/hyperspy/hyperspy/gui_ipywidgets/tools.py in on_remove_clicked(b)
    416 
    417     def on_remove_clicked(b):
--> 418         obj.apply()
    419     remove.on_click(on_remove_clicked)
    420     labeled_spline_order = labelme("Spline order", spline_order)

/Users/thomas/hyperspy/hyperspy/signal_tools.py in apply(self)
   1048 
   1049     def apply(self):
-> 1050         self.signal()[:] = self.get_interpolated_spectrum()
   1051         self.signal.events.data_changed.trigger(obj=self.signal)
   1052         self.update_spectrum_line()

/Users/thomas/hyperspy/hyperspy/signal_tools.py in get_interpolated_spectrum(self, axes_manager)
    997         data = self.signal().copy()
    998         axis = self.signal.axes_manager.signal_axes[0]
--> 999         left, right = self.get_interpolation_range()
   1000         if self.kind == 'linear':
   1001             pad = 1

/Users/thomas/hyperspy/hyperspy/signal_tools.py in get_interpolation_range(self)
    981         axis = self.signal.axes_manager.signal_axes[0]
    982         if np.isnan(self.ss_left_value) or np.isnan(self.ss_right_value):
--> 983             left = self.argmax - self.default_spike_width
    984             right = self.argmax + self.default_spike_width
    985         else:

TypeError: unsupported operand type(s) for -: 'NoneType' and 'int'