diff --git a/libs/microphone/microphone.cpp b/libs/microphone/microphone.cpp
index eed5ed52b7e..9f735608c9f 100644
--- a/libs/microphone/microphone.cpp
+++ b/libs/microphone/microphone.cpp
@@ -5,9 +5,6 @@
 #include "LevelDetectorSPL.h"
 #endif
 
-#define MICROPHONE_MIN 52.0f
-#define MICROPHONE_MAX 120.0f
-
 enum class DetectedSound {
     //% block="loud"
     Loud = 2,
@@ -23,6 +20,20 @@ enum class SoundThreshold {
 };
 namespace input {
 
+#if MICROBIT_CODAL
+bool didInit;
+
+void init() {
+    if (didInit) {
+        return;
+    }
+
+    didInit = true;
+    uBit.audio.levelSPL->setUnit(LEVEL_DETECTOR_SPL_8BIT);
+}
+
+#endif
+
 /**
 * Registers an event that runs when a sound is detected
 */
@@ -33,6 +44,7 @@ namespace input {
 //% group="micro:bit (V2)"
 void onSound(DetectedSound sound, Action handler) {
 #if MICROBIT_CODAL
+    init();
     const auto thresholdType = sound == DetectedSound::Loud ? LEVEL_THRESHOLD_HIGH : LEVEL_THRESHOLD_LOW;
     registerWithDal(DEVICE_ID_SYSTEM_LEVEL_DETECTOR, thresholdType, handler);
 #else
@@ -50,12 +62,8 @@ void onSound(DetectedSound sound, Action handler) {
 //% group="micro:bit (V2)"
 int soundLevel() {
 #if MICROBIT_CODAL
-    LevelDetectorSPL* level = uBit.audio.levelSPL;
-    if (NULL == level)
-        return 0;
-    const int micValue = level->getValue();
-    const int scaled = max(MICROPHONE_MIN, min(micValue, MICROPHONE_MAX)) - MICROPHONE_MIN;
-    return min(0xff, scaled * 0xff / (MICROPHONE_MAX - MICROPHONE_MIN));
+    init();
+    return uBit.audio.levelSPL->getValue();
 #else
     target_panic(PANIC_VARIANT_NOT_SUPPORTED);
     return 0;
@@ -74,16 +82,14 @@ int soundLevel() {
 //% group="micro:bit (V2)"
 void setSoundThreshold(SoundThreshold sound, int threshold) {
 #if MICROBIT_CODAL
+    init();
     LevelDetectorSPL* level = uBit.audio.levelSPL;
     if (NULL == level)
         return;
-
-    threshold = max(0, min(0xff, threshold));
-    const int scaled = MICROPHONE_MIN + threshold * (MICROPHONE_MAX - MICROPHONE_MIN) / 0xff;
     if (SoundThreshold::Loud == sound)
-        level->setHighThreshold(scaled);
+        level->setHighThreshold(threshold);
     else
-        level->setLowThreshold(scaled);
+        level->setLowThreshold(threshold);
 #else
     target_panic(PANIC_VARIANT_NOT_SUPPORTED);
 #endif