@Sylvain,

 Thanks for your feedback. And I try to run 'setup.py test' in the master branch, it also failed in several testcases. I just pasted part of result.

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FAIL: test_SPDIF_in_port_label (checkbox_support.parsers.tests.test_pactl.AttributeTests)                                                                     
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Traceback (most recent call last):                                             
  File "/work/source/gits/checkbox-dev/checkbox-support/checkbox_support/parsers/tests/test_pactl.py", line 522, in test_SPDIF_in_port_label                  
    self.assertEqual(attr.value[0].latency_offset, 0)                                                                                                         
AssertionError: ([0], {}) != 0                                                 
                                                                                                                                                              
======================================================================                                                                                        FAIL: test_many_ports (checkbox_support.parsers.tests.test_pactl.AttributeTests)                                                                              
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Traceback (most recent call last):                                                                                                                            
  File "/work/source/gits/checkbox-dev/checkbox-support/checkbox_support/parsers/tests/test_pactl.py", line 443, in test_many_ports                           
    self.assertEqual(attr.value[0].availability, '')                                                                                                          
AssertionError: ([''], {}) != ''                                               
                                                                                                                                                              
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FAIL: test_one_port (checkbox_support.parsers.tests.test_pactl.AttributeTests)                                                                                
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Traceback (most recent call last):                                                                                                                            
  File "/work/source/gits/checkbox-dev/checkbox-support/checkbox_support/parsers/tests/test_pactl.py", line 421, in test_one_port                             
    self.assertEqual(attr.value[0].availability, 'available')                                                                                                 
AssertionError: (['available'], {}) != 'available'