diff --git a/src/audio/AudioManager.h b/src/audio/AudioManager.h
index eabdecf5..d7a744cd 100644
--- a/src/audio/AudioManager.h
+++ b/src/audio/AudioManager.h
@@ -379,7 +379,7 @@ public:
 	void Service();
 	void ServiceCollisions();
 	void ServicePoliceRadio();
-	void ServicePoliceRadioChannel(int32 wantedLevel);
+	void ServicePoliceRadioChannel(uint8 wantedLevel);
 	void ServiceSoundEffects();
 	int8 SetCurrent3DProvider(uint8 which);
 	void SetDynamicAcousticModelingStatus(uint8 status);
diff --git a/src/audio/PoliceRadio.cpp b/src/audio/PoliceRadio.cpp
index 64b91e83..781040d6 100644
--- a/src/audio/PoliceRadio.cpp
+++ b/src/audio/PoliceRadio.cpp
@@ -153,7 +153,7 @@ cAudioManager::ServicePoliceRadio()
 }
 
 void
-cAudioManager::ServicePoliceRadioChannel(int32 wantedLevel)
+cAudioManager::ServicePoliceRadioChannel(uint8 wantedLevel)
 {
 	bool processed = false;
 	uint32 sample;