diff --git a/plugin_sa/game_sa/AudioTypes.h b/plugin_sa/game_sa/AudioTypes.h
new file mode 100644
index 00000000..67204882
--- /dev/null
+++ b/plugin_sa/game_sa/AudioTypes.h
@@ -0,0 +1,38 @@
+/*
+    Plugin-SDK (Grand Theft Auto San Andreas) header file
+    Authors: GTA Community. See more here
+    https://github.com/DK22Pac/plugin-sdk
+    Do not delete this comment block. Respect others' work!
+*/
+#pragma once
+#include "PluginBase.h"
+
+struct tBeat {
+	UInt32 time;
+	UInt32 key;
+};
+VALIDATE_OFFSET(tBeat, time, 0x0);
+VALIDATE_OFFSET(tBeat, key, 0x4);
+VALIDATE_SIZE(tBeat, 0x8);
+
+struct tBeatInfo {
+    tBeat beatWindow[20];
+    Int32 isBeatInfoPresent;
+    Int32 beatTypeThisFrame;
+    Int32 beatNumber;
+};
+VALIDATE_OFFSET(tBeatInfo, beatWindow, 0x0);
+VALIDATE_OFFSET(tBeatInfo, isBeatInfoPresent, 0xA0);
+VALIDATE_OFFSET(tBeatInfo, beatTypeThisFrame, 0xA4);
+VALIDATE_OFFSET(tBeatInfo, beatNumber, 0xA8);
+VALIDATE_SIZE(tBeatInfo, 0xAC);
+
+struct tTrackInfo {
+    tBeat beats[1000];
+	UInt32 field_1F40[16];
+    UInt16 field_1F80;
+};
+VALIDATE_OFFSET(tTrackInfo, beats, 0x0);
+VALIDATE_OFFSET(tTrackInfo, field_1F40, 0x1F40);
+VALIDATE_OFFSET(tTrackInfo, field_1F80, 0x1F80);
+VALIDATE_SIZE(tTrackInfo, 0x1F84);
diff --git a/plugin_sa/game_sa/CAEAudioHardware.h b/plugin_sa/game_sa/CAEAudioHardware.h
index 50c90b71..a603d5cc 100644
--- a/plugin_sa/game_sa/CAEAudioHardware.h
+++ b/plugin_sa/game_sa/CAEAudioHardware.h
@@ -13,11 +13,11 @@
 
 class PLUGIN_API CAEAudioHardware {
 public:
-    unsigned char field_0;
-    char m_bDisableEffectsLoading;
-    char field_2;
-    char field_3;
-    char field_4;
+    bool m_bInitialised;
+    bool m_bDisableEffectsLoading;
+    bool m_bPrevMaxSecondarySlowFadeout;
+    bool m_bPrevMaxGlobalSlowFadeout;
+    bool m_bHardwareMixAvailable;
     char m_nReverbEnvironment;
     short m_awChannelFlags[64];
     short field_86;
@@ -26,16 +26,16 @@ class PLUGIN_API CAEAudioHardware {
     unsigned short m_nNumChannels;
     short m_anNumSoundsInSlot[64];
     float m_afChannelVolumes[64];
-    int field_210[64];
+    float m_afChannelGains[64]; // linear volume gain (10 ^ (dB / 20))
     float m_afChannelsFrqScalingFactor[64];
     float m_fMusicMasterScalingFactor;
     float m_fEffectMasterScalingFactor;
     float m_fMusicFaderScalingFactor;
     float m_fEffectsFaderScalingFactor;
     float m_fStreamFaderScalingFactor;
-    float m_fNonStreamFaderScalingFactor;
-    float field_428;
-    float field_42C;
+    float m_fNonStreamFaderScalingFactor; // order swapped with m_fStreamFaderScalingFactor?
+    float m_fPrevMaxVolumeSecondary;
+    float m_fPrevMaxVolumeGlobal;
     short m_aBankSlotIds[300];
     short m_aSoundTypes[300];
     short m_anVirtualChannelSoundLoopStartTimes[300];
@@ -64,11 +64,11 @@ class PLUGIN_API CAEAudioHardware {
 public:
     int GetActiveTrackID();
 };
-VALIDATE_OFFSET(CAEAudioHardware, field_0, 0x0);
+VALIDATE_OFFSET(CAEAudioHardware, m_bInitialised, 0x0);
 VALIDATE_OFFSET(CAEAudioHardware, m_bDisableEffectsLoading, 0x1);
-VALIDATE_OFFSET(CAEAudioHardware, field_2, 0x2);
-VALIDATE_OFFSET(CAEAudioHardware, field_3, 0x3);
-VALIDATE_OFFSET(CAEAudioHardware, field_4, 0x4);
+VALIDATE_OFFSET(CAEAudioHardware, m_bPrevMaxSecondarySlowFadeout, 0x2);
+VALIDATE_OFFSET(CAEAudioHardware, m_bPrevMaxGlobalSlowFadeout, 0x3);
+VALIDATE_OFFSET(CAEAudioHardware, m_bHardwareMixAvailable, 0x4);
 VALIDATE_OFFSET(CAEAudioHardware, m_nReverbEnvironment, 0x5);
 VALIDATE_OFFSET(CAEAudioHardware, m_awChannelFlags, 0x6);
 VALIDATE_OFFSET(CAEAudioHardware, field_86, 0x86);
@@ -77,7 +77,7 @@ VALIDATE_OFFSET(CAEAudioHardware, m_wNumAvailableChannels, 0x8C);
 VALIDATE_OFFSET(CAEAudioHardware, m_nNumChannels, 0x8E);
 VALIDATE_OFFSET(CAEAudioHardware, m_anNumSoundsInSlot, 0x90);
 VALIDATE_OFFSET(CAEAudioHardware, m_afChannelVolumes, 0x110);
-VALIDATE_OFFSET(CAEAudioHardware, field_210, 0x210);
+VALIDATE_OFFSET(CAEAudioHardware, m_afChannelGains, 0x210);
 VALIDATE_OFFSET(CAEAudioHardware, m_afChannelsFrqScalingFactor, 0x310);
 VALIDATE_OFFSET(CAEAudioHardware, m_fMusicMasterScalingFactor, 0x410);
 VALIDATE_OFFSET(CAEAudioHardware, m_fEffectMasterScalingFactor, 0x414);
@@ -85,8 +85,8 @@ VALIDATE_OFFSET(CAEAudioHardware, m_fMusicFaderScalingFactor, 0x418);
 VALIDATE_OFFSET(CAEAudioHardware, m_fEffectsFaderScalingFactor, 0x41C);
 VALIDATE_OFFSET(CAEAudioHardware, m_fStreamFaderScalingFactor, 0x420);
 VALIDATE_OFFSET(CAEAudioHardware, m_fNonStreamFaderScalingFactor, 0x424);
-VALIDATE_OFFSET(CAEAudioHardware, field_428, 0x428);
-VALIDATE_OFFSET(CAEAudioHardware, field_42C, 0x42C);
+VALIDATE_OFFSET(CAEAudioHardware, m_fPrevMaxVolumeSecondary, 0x428);
+VALIDATE_OFFSET(CAEAudioHardware, m_fPrevMaxVolumeGlobal, 0x42C);
 VALIDATE_OFFSET(CAEAudioHardware, m_aBankSlotIds, 0x430);
 VALIDATE_OFFSET(CAEAudioHardware, m_aSoundTypes, 0x688);
 VALIDATE_OFFSET(CAEAudioHardware, m_anVirtualChannelSoundLoopStartTimes, 0x8E0);
diff --git a/plugin_sa/game_sa/CAERadioTrackManager.cpp b/plugin_sa/game_sa/CAERadioTrackManager.cpp
index 2a539dd5..47a81ce9 100644
--- a/plugin_sa/game_sa/CAERadioTrackManager.cpp
+++ b/plugin_sa/game_sa/CAERadioTrackManager.cpp
@@ -18,8 +18,8 @@ char *CAERadioTrackManager::GetRadioStationName(signed char id)
 	return ((char *(__thiscall *)(CAERadioTrackManager *, signed char))0x4E9E10)(this, id);
 }
 
-void CAERadioTrackManager::StartRadio(int stationId, float bass, int arg, char unused) {
-    plugin::CallMethod<0x4EB3C0, CAERadioTrackManager*, int, float, int, char>(this, stationId, bass, arg, unused);
+void CAERadioTrackManager::StartRadio(eRadioID stationId, float bass, int arg, char unused) {
+    plugin::CallMethod<0x4EB3C0, CAERadioTrackManager*, eRadioID, float, int, char>(this, stationId, bass, arg, unused);
 }
 
 void CAERadioTrackManager::StopRadio(tVehicleAudioSettings* settings, char arg) {
diff --git a/plugin_sa/game_sa/CAERadioTrackManager.h b/plugin_sa/game_sa/CAERadioTrackManager.h
index 6230134e..a43af44d 100644
--- a/plugin_sa/game_sa/CAERadioTrackManager.h
+++ b/plugin_sa/game_sa/CAERadioTrackManager.h
@@ -8,6 +8,7 @@
 
 #include "PluginBase.h"
 #include "CAEVehicleAudioEntity.h"
+#include "eRadioID.h"
 
 struct PLUGIN_API tRadioSettings {
     Int32 TrackIDs[5];
@@ -16,7 +17,7 @@ struct PLUGIN_API tRadioSettings {
     Int32 PlayTime;
     Int32 TrackLengthMs;
     UInt8 TrackFlags;
-    Int8 StationID; // eRadioID
+    eRadioID StationID;
     Int8 BassSetting;
     Int8 _pad27;
     float BassFactor;
@@ -110,7 +111,7 @@ class PLUGIN_API CAERadioTrackManager {
 public:
     bool IsVehicleRadioActive();
     char* GetRadioStationName(signed char id);
-    void StartRadio(int stationId, float bass, int arg, char unused);
+    void StartRadio(eRadioID stationId, float bass, int arg, char unused);
     void StopRadio(tVehicleAudioSettings* settings, char arg);
 
     static void Load();
diff --git a/plugin_sa/game_sa/CAudioEngine.cpp b/plugin_sa/game_sa/CAudioEngine.cpp
index 733da50d..0c4136d5 100644
--- a/plugin_sa/game_sa/CAudioEngine.cpp
+++ b/plugin_sa/game_sa/CAudioEngine.cpp
@@ -37,8 +37,8 @@ void CAudioEngine::SetRadioAutoRetuneOnOff(bool on) {
     plugin::CallMethod<0x506F80, CAudioEngine*, bool>(this, on);
 }
 
-void CAudioEngine::RetuneRadio(char stationId) {
-    plugin::CallMethod<0x507E10, CAudioEngine*, char>(this, stationId);
+void CAudioEngine::RetuneRadio(eRadioID stationId) {
+    plugin::CallMethod<0x507E10, CAudioEngine*, eRadioID>(this, stationId);
 }
 
 CReference* CAudioEngine::ReportFrontendAudioEvent(int id, float volume, float speed) {
@@ -58,8 +58,8 @@ void CAudioEngine::ServiceLoadingTune(float fade) {
     plugin::CallMethod<0x5078A0, CAudioEngine*, float>(this, fade);
 }
 
-void CAudioEngine::StartRadio(int radioStation, char arg) {
-    plugin::CallMethod<0x507DC0, CAudioEngine*, int, char>(this, radioStation, arg);
+void CAudioEngine::StartRadio(eRadioID radioStation, char arg) {
+    plugin::CallMethod<0x507DC0, CAudioEngine*, eRadioID, char>(this, radioStation, arg);
 }
 
 void CAudioEngine::StopRadio(tVehicleAudioSettings* settings, bool arg) {
diff --git a/plugin_sa/game_sa/CAudioEngine.h b/plugin_sa/game_sa/CAudioEngine.h
index 03479735..5f9f772a 100644
--- a/plugin_sa/game_sa/CAudioEngine.h
+++ b/plugin_sa/game_sa/CAudioEngine.h
@@ -6,6 +6,7 @@
 */
 #pragma once
 #include "PluginBase.h"
+#include "AudioTypes.h"
 #include "CAEFrontendAudioEntity.h"
 #include "CAEPedlessSpeechAudioEntity.h"
 #include "CAETwinLoopSoundEntity.h"
@@ -13,19 +14,16 @@
 #include "CAECollisionAudioEntity.h"
 #include "CAEVehicleAudioEntity.h"
 #include "eAudioEvents.h"
+#include "eRadioID.h"
 
 class PLUGIN_API CAudioEngine {
 public:
-    char field_0;
-    char field_1;
-    char m_nCurrentRadiostationId;
-    char field_3;
-    int field_4;
-    char field_8[152];
-    char field_A0;
-    char field_A1[15];
-    char field_B0;
-    char field_B1[3];
+    bool m_bPlayingMissionCompleteTrack;
+    bool m_bStoppingMissionCompleteTrack;
+    eRadioID m_nCurrentRadiostationId;
+    eRadioID m_nSavedRadioStationId;
+    int m_nBackgroundAudioChannel;
+    tBeatInfo m_beatInfo;
     CAEFrontendAudioEntity m_FrontendAudio;
     CAETwinLoopSoundEntity field_150;
     CAETwinLoopSoundEntity field_1F8;
@@ -44,12 +42,12 @@ class PLUGIN_API CAudioEngine {
     void SetMusicMasterVolume(char volume);
     void SetBassEnhanceOnOff(bool on);
     void SetRadioAutoRetuneOnOff(bool on);
-    void RetuneRadio(char stationId);
+    void RetuneRadio(eRadioID stationId);
     CReference* ReportFrontendAudioEvent(int id, float volume, float speed);
     void ReportMissionAudioEvent(eAudioEvents audioEvent, CVector const* coords);
     void Service();
     void ServiceLoadingTune(float fade);
-    void StartRadio(int radioStation, char arg);
+    void StartRadio(eRadioID radioStation, char arg);
     void StopRadio(tVehicleAudioSettings* settings, bool arg);
     bool IsRadioRetuneInProgress();
     bool IsLoadingTuneActive();
@@ -62,16 +60,12 @@ class PLUGIN_API CAudioEngine {
     void SetMusicFaderScalingFactor(float value);
     void SetEffectsFaderScalingFactor(float value);
 };
-VALIDATE_OFFSET(CAudioEngine, field_0, 0x0);
-VALIDATE_OFFSET(CAudioEngine, field_1, 0x1);
+VALIDATE_OFFSET(CAudioEngine, m_bPlayingMissionCompleteTrack, 0x0);
+VALIDATE_OFFSET(CAudioEngine, m_bStoppingMissionCompleteTrack, 0x1);
 VALIDATE_OFFSET(CAudioEngine, m_nCurrentRadiostationId, 0x2);
-VALIDATE_OFFSET(CAudioEngine, field_3, 0x3);
-VALIDATE_OFFSET(CAudioEngine, field_4, 0x4);
-VALIDATE_OFFSET(CAudioEngine, field_8, 0x8);
-VALIDATE_OFFSET(CAudioEngine, field_A0, 0xA0);
-VALIDATE_OFFSET(CAudioEngine, field_A1, 0xA1);
-VALIDATE_OFFSET(CAudioEngine, field_B0, 0xB0);
-VALIDATE_OFFSET(CAudioEngine, field_B1, 0xB1);
+VALIDATE_OFFSET(CAudioEngine, m_nSavedRadioStationId, 0x3);
+VALIDATE_OFFSET(CAudioEngine, m_nBackgroundAudioChannel, 0x4);
+VALIDATE_OFFSET(CAudioEngine, m_beatInfo, 0x8);
 VALIDATE_OFFSET(CAudioEngine, m_FrontendAudio, 0xB4);
 VALIDATE_OFFSET(CAudioEngine, field_150, 0x150);
 VALIDATE_OFFSET(CAudioEngine, field_1F8, 0x1F8);