diff --git a/inc/MicroBitAudio.h b/inc/MicroBitAudio.h
index f3623767..baed2d1b 100644
--- a/inc/MicroBitAudio.h
+++ b/inc/MicroBitAudio.h
@@ -55,7 +55,7 @@ namespace codal
         public:
         static MicroBitAudio    *instance;      // Primary instance of MicroBitAudio, on demand activated.
         Mixer2                  mixer;          // Multi channel audio mixer
-        NRF52ADCChannel *mic;                   // Microphone ADC Channel from uBit.IO
+        NRF52ADCChannel         *mic;           // Microphone ADC Channel from uBit.IO
         StreamNormalizer        *processor;     // Stream Normaliser instance
         StreamSplitter          *splitter;      // Stream Splitter instance (8bit normalized output)
         StreamSplitter          *rawSplitter;   // Stream Splitter instance (raw input)
@@ -184,6 +184,8 @@ namespace codal
           * Puts the component in (or out of) sleep (low power) mode.
           */
         virtual int setSleep(bool doSleep) override;
+
+        virtual void periodicCallback();
     };
 }
 
diff --git a/source/MicroBitAudio.cpp b/source/MicroBitAudio.cpp
index 4e30a31f..23aaa2ea 100644
--- a/source/MicroBitAudio.cpp
+++ b/source/MicroBitAudio.cpp
@@ -55,6 +55,9 @@ MicroBitAudio::MicroBitAudio(NRF52Pin &pin, NRF52Pin &speaker, NRF52ADC &adc, NR
     if (MicroBitAudio::instance == NULL)
         MicroBitAudio::instance = this;
 
+    // Request a periodic callback
+    status |= DEVICE_COMPONENT_STATUS_SYSTEM_TICK;
+
     synth.allowEmptyBuffers(true);
 
     mic = adc.getChannel(microphone, false);
@@ -85,6 +88,15 @@ MicroBitAudio::MicroBitAudio(NRF52Pin &pin, NRF52Pin &speaker, NRF52ADC &adc, NR
     splitter = new StreamSplitter(processor->output, DEVICE_ID_SPLITTER);
 }
 
+void MicroBitAudio::periodicCallback()
+{
+    if (mic->isEnabled() && !micEnabled)
+        activateMic();
+
+    if (!mic->isEnabled() && micEnabled)
+        deactivateMic();
+}
+
 void MicroBitAudio::activateMic(){
     runmic.setDigitalValue(1);
     runmic.setHighDrive(true);