Code review comment for ~stanley31/checkbox-support:0909_modify_audio_settings

attached test results of the unit test:

test_volume_regex_trusty (test_audio_settings.RegexTest)
Testing pactl 4.0 output ... ok
test_volume_regex_xenial (test_audio_settings.RegexTest)
Testing pactl 8.0 output ... ok
test_desktop_bionic_x13 (test_audio_settings.SetProfileTest)
Bionic system with a Intel UHD Graphics chipset, it's DMIC system. ... ok
test_desktop_precise_radeon_available (test_audio_settings.SetProfileTest)
Home-made system running Precise with a Radeon card. ... ok
test_desktop_precise_radeon_not_available (test_audio_settings.SetProfileTest)
Home-made system running Precise with a Radeon card. ... ok
test_desktop_precise_xps1340 (test_audio_settings.SetProfileTest)
Precise system with a Nvidia chipset. ... ok
test_desktop_raring_t430s_available (test_audio_settings.SetProfileTest)
Raring system with a Mini-DisplayPort. ... ok
test_desktop_raring_t430s_not_available (test_audio_settings.SetProfileTest)
Raring system with a Mini-DisplayPort. ... ok

----------------------------------------------------------------------
Ran 8 tests in 7.784s

OK