Reduce default microphone volume

BUG=
TEST=

Review URL: http://codereview.chromium.org/3532012
diff --git a/pulse/default-cros.pa b/pulse/default-cros.pa
index ad471f8..92e29d1 100644
--- a/pulse/default-cros.pa
+++ b/pulse/default-cros.pa
@@ -29,7 +29,7 @@
 
 ### Automatically restore the volume of streams and devices.
 ### Set the default volume and mute states for new devices.
-load-module module-device-restore default_sink_volume=55706 default_sink_muted=n default_source_volume=65537 default_source_muted=n
+load-module module-device-restore default_sink_volume=55706 default_sink_muted=n default_source_volume=46349 default_source_muted=n
 load-module module-stream-restore
 load-module module-card-restore