audiotest: unmute when setting the volume.

Unset mute when setting the volume levels for the test.

BUG=none
TEST=desktopui_AudioFeedback

Change-Id: I8390d537a81d0d5e57e27f05706d9d21006f1197
Signed-off-by: Dylan Reid <dgreid@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/37503
diff --git a/client/cros/audio/audio_helper.py b/client/cros/audio/audio_helper.py
index 9a83688..0afa70f 100644
--- a/client/cros/audio/audio_helper.py
+++ b/client/cros/audio/audio_helper.py
@@ -102,6 +102,7 @@
         logging.info('Setting capture gain to %d' % capture)
         utils.system('/usr/bin/cras_test_client --capture_gain %d' % capture)
         utils.system('/usr/bin/cras_test_client --dump_server_info')
+        utils.system('/usr/bin/cras_test_client --mute 0')
         utils.system('amixer -c 0 contents')
 
     def get_jack_status(self, jack_reg_exp):