diff --git a/src/audio/AudioLogic.cpp b/src/audio/AudioLogic.cpp
index 5ea03aff..174bd5fa 100644
--- a/src/audio/AudioLogic.cpp
+++ b/src/audio/AudioLogic.cpp
@@ -2796,7 +2796,7 @@ cAudioManager::SetupJumboTaxiSound(uint8 vol)
 }
 
 bool
-cAudioManager::SetupJumboWhineSound(uint8 emittingVol, int32 freq)
+cAudioManager::SetupJumboWhineSound(uint8 emittingVol, uint32 freq)
 {
 	const float SOUND_INTENSITY = 170.0f;
 
@@ -2828,7 +2828,7 @@ cAudioManager::SetupJumboWhineSound(uint8 emittingVol, int32 freq)
 }
 
 bool
-cAudioManager::SetupJumboEngineSound(uint8 vol, int32 freq)
+cAudioManager::SetupJumboEngineSound(uint8 vol, uint32 freq)
 {
 	const float SOUND_INTENSITY = 180.0f;
 	if (m_sQueueSample.m_fDistance >= SOUND_INTENSITY)
diff --git a/src/audio/AudioManager.h b/src/audio/AudioManager.h
index b6bbef8f..a1aa96f5 100644
--- a/src/audio/AudioManager.h
+++ b/src/audio/AudioManager.h
@@ -457,11 +457,11 @@ public:
 	void SetUpLoopingCollisionSound(const cAudioCollision &col, uint8 counter);
 	void SetUpOneShotCollisionSound(const cAudioCollision &col);
 	bool SetupCrimeReport();
-	bool SetupJumboEngineSound(uint8 vol, int32 freq);
+	bool SetupJumboEngineSound(uint8 vol, uint32 freq);
 	bool SetupJumboFlySound(uint8 emittingVol);
 	bool SetupJumboRumbleSound(uint8 emittingVol);
 	bool SetupJumboTaxiSound(uint8 vol);
-	bool SetupJumboWhineSound(uint8 emittingVol, int32 freq);
+	bool SetupJumboWhineSound(uint8 emittingVol, uint32 freq);
 	void SetupPedComments(cPedParams *params, uint32 sound);
 	void SetupSuspectLastSeenReport();