PyUSB IR problem macbook

Python 2.7.2 (default, Jul 26 2011, 17:12:52)
[GCC 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.9)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> import usb.core,usb.util
>>> dev = usb.core.find(idVendor=0x05ac, idProduct=0x8242)
>>> dev.set_configuration()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/usb/core.py", line 530, in set_configuration
    self._ctx.managed_set_configuration(self, configuration)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/usb/core.py", line 92, in managed_set_configuration
    self.backend.set_configuration(self.handle, cfg.bConfigurationValue)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/usb/_debug.py", line 52, in do_trace
    return f(*args, **named_args)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/usb/backend/libusb10.py", line 455, in set_configuration
    _check(_lib.libusb_set_configuration(dev_handle, config_value))
  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/usb/backend/libusb10.py", line 357, in _check
    raise USBError(_str_error[retval.value])
usb.core.USBError: Unknown error
>>> dev.iProduct
2
>>> dev.idProduct
33346
>>> dev.idVendor
1452
>>> dev.iSerialNumber
0
#touch any button on the control
>>> dev.set_configuration()
>>> dev.iProduct
2
>>> dev.idProduct
33346
>>> dev.iSerialNumber
0
>>> dev.iSerialNumber
0