diff --git a/model/MicroBit.cpp b/model/MicroBit.cpp
index 79f63bb2..ef018255 100644
--- a/model/MicroBit.cpp
+++ b/model/MicroBit.cpp
@@ -202,7 +202,22 @@ int MicroBit::init()
     }
 
     // Seed our random number generator
-    seedRandom();
+    if(ble_running())
+    {
+        // Readings from different sensors
+        int16_t accelerometerX = accelerometer.getX();
+        int16_t accelerometerY = accelerometer.getY();
+        int16_t accelerometerZ = accelerometer.getZ();
+        int16_t temperatureValue = thermometer.getTemperature();
+        int16_t microphoneValue = io.MICROPHONE.getAnalogValue();
+        // Combine sensor values using XOR
+        uint32_t r = accelerometerX ^ accelerometerY ^ accelerometerZ ^ temperatureValue ^ microphoneValue;
+        seedRandom(r);
+    }
+    else
+    {
+        seedRandom();
+    }
 
     // Create an event handler to trap any handlers being created for I2C services.
     // We do this to enable initialisation of those services only when they're used,
diff --git a/source/MicroBitDevice.cpp b/source/MicroBitDevice.cpp
index 7e7fa37f..2bd4ccae 100644
--- a/source/MicroBitDevice.cpp
+++ b/source/MicroBitDevice.cpp
@@ -68,19 +68,7 @@ void MicroBitDevice::seedRandom()
 {
     uint32_t r = 0xBBC5EED;
 
-    if(ble_running())
-    {
-        // Readings from different sensors
-        int16_t accelerometerX = uBit.accelerometer.getX();
-        int16_t accelerometerY = uBit.accelerometer.getY();
-        int16_t accelerometerZ = uBit.accelerometer.getZ();
-        int16_t temperatureValue = uBit.thermometer.getTemperature();
-        int16_t microphoneValue = uBit.io.MICROPHONE.getAnalogValue();
-
-        // Combine sensor values using XOR
-        r = accelerometerX ^ accelerometerY ^ accelerometerZ ^ temperatureValue ^ microphoneValue;
-    }
-    else
+    if(!ble_running())
     {
         // Start the Random number generator. No need to leave it running... I hope. :-)
         NRF_RNG->TASKS_START = 1;