diff --git a/speech/microphone/requirements.txt b/speech/microphone/requirements.txt
index 981371627d4e..b6e4390197e3 100644
--- a/speech/microphone/requirements.txt
+++ b/speech/microphone/requirements.txt
@@ -1,4 +1,4 @@
 google-cloud-speech==2.3.0
 pyaudio==0.2.11
-six==1.15.0
+six==1.16.0