PinNonPhysical: no physical pins exist for GPIO

[velkrosmaak]

I'm trying to set this up on a new raspbian install on a B+. Suspecting this might be because of differences in pin assignments on a B+ compared to subsequent versions.

When I run the script (with python 2 or 3) I get the following error:

/usr/lib/python2.7/dist-packages/gpiozero/pins/pi.py:270: PinNonPhysical: no physical pins exist for GPIO26
'no physical pins exist for %s' % repr(self)))
/usr/lib/python2.7/dist-packages/gpiozero/pins/pi.py:270: PinNonPhysical: no physical pins exist for GPIO19
'no physical pins exist for %s' % repr(self)))
/usr/lib/python2.7/dist-packages/gpiozero/pins/pi.py:270: PinNonPhysical: no physical pins exist for GPIO16
'no physical pins exist for %s' % repr(self)))
Traceback (most recent call last):
File "gpophone.py", line 15, in
hook = gpiozero.Button(pin_hook)
File "/usr/lib/python2.7/dist-packages/gpiozero/devices.py", line 124, in call
self = super(GPIOMeta, cls).call(*args, **kwargs)
File "/usr/lib/python2.7/dist-packages/gpiozero/input_devices.py", line 432, in init
bounce_time=bounce_time, pin_factory=pin_factory)
File "/usr/lib/python2.7/dist-packages/gpiozero/mixins.py", line 383, in init
super(HoldMixin, self).init(*args, **kwargs)
File "/usr/lib/python2.7/dist-packages/gpiozero/input_devices.py", line 186, in init
self.pin.when_changed = self._pin_changed
File "/usr/lib/python2.7/dist-packages/gpiozero/pins/init.py", line 450, in
lambda self, value: self._set_when_changed(value),
File "/usr/lib/python2.7/dist-packages/gpiozero/pins/pi.py", line 314, in _set_when_changed
self._enable_event_detect()
File "/usr/lib/python2.7/dist-packages/gpiozero/pins/rpigpio.py", line 250, in _enable_event_detect
bouncetime=self._bounce)
RuntimeError: Failed to add edge detection

Do you have any suggestions on what I could try to resolve this? Cheers!