diff --git a/inc/MicroBitAudio.h b/inc/MicroBitAudio.h
index 0a0d70c3..0e56c2d4 100644
--- a/inc/MicroBitAudio.h
+++ b/inc/MicroBitAudio.h
@@ -185,11 +185,6 @@ namespace codal
          */
         bool isPinEnabled();
 
-        /**
-         * Hook deep sleep events so we can manually turn off/on the microphone power pin.
-         */
-        int deepSleepCallback( deepSleepCallbackReason reason, deepSleepCallbackData *data);
-
         /**
           * Puts the component in (or out of) sleep (low power) mode.
           */
diff --git a/source/MicroBitAudio.cpp b/source/MicroBitAudio.cpp
index 93a22266..b5543846 100644
--- a/source/MicroBitAudio.cpp
+++ b/source/MicroBitAudio.cpp
@@ -224,12 +224,6 @@ MicroBitAudio::~MicroBitAudio()
     }
 }
 
-int MicroBitAudio::deepSleepCallback( deepSleepCallbackReason reason, deepSleepCallbackData *data)
-{
-    deactivateMic();
-}
-
-
 int MicroBitAudio::setSleep(bool doSleep)
 {
     if (doSleep)
@@ -244,6 +238,7 @@ int MicroBitAudio::setSleep(bool doSleep)
           delete pwm;
           pwm = NULL;
       }
+      deactivateMic();
     }
     else
     {
@@ -252,6 +247,7 @@ int MicroBitAudio::setSleep(bool doSleep)
           status &= ~MICROBIT_AUDIO_STATUS_DEEPSLEEP;
           enable();
       }
+      activateMic();
     }
    
     return DEVICE_OK;