diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5ad14ec..b776fa0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -57,6 +57,7 @@ set(TETRIS_SOURCES
     src/graphics/renderers/SyncLineRenderer.cpp
     src/graphics/renderers/UIRenderer.cpp
     src/audio/Audio.cpp
+    src/audio/AudioManager.cpp
     src/renderer/SDLRenderer.cpp
     src/gameplay/effects/LineEffect.cpp
     src/audio/SoundEffect.cpp
diff --git a/src/audio/Audio.cpp b/src/audio/Audio.cpp
index 582f7b5..15570b5 100644
--- a/src/audio/Audio.cpp
+++ b/src/audio/Audio.cpp
@@ -118,6 +118,7 @@ static bool decodeMP3(const std::string& path, std::vector<int16_t>& outPCM, int
     outCh = static_cast<int>(clientFormat.mChannelsPerFrame);
     return !outPCM.empty();
 }
+
 #else
 static bool decodeMP3(const std::string& path, std::vector<int16_t>& outPCM, int& outRate, int& outCh){
     (void)outPCM; (void)outRate; (void)outCh; (void)path;
@@ -184,6 +185,8 @@ void Audio::skipToNextTrack(){
 void Audio::toggleMute(){ muted=!muted; }
 void Audio::setMuted(bool m){ muted=m; }
 
+bool Audio::isMuted() const { return muted; }
+
 void Audio::nextTrack(){
     if(tracks.empty()) { current = -1; return; }
     // Try every track once to find a decodable one
diff --git a/src/audio/Audio.h b/src/audio/Audio.h
index 35f520a..2e1a176 100644
--- a/src/audio/Audio.h
+++ b/src/audio/Audio.h
@@ -32,29 +32,27 @@ public:
     void setSoundVolume(float volume) override;
     bool isMusicPlaying() const override;
 
-    // Existing Audio class methods
-    bool init();                  // initialize backend (MF on Windows)
-    void addTrack(const std::string& path); // decode MP3 -> PCM16 stereo 44100
-    void addTrackAsync(const std::string& path); // add track for background loading
-    void startBackgroundLoading(); // start background thread for loading
-    void waitForLoadingComplete(); // wait for all tracks to finish loading
-    bool isLoadingComplete() const; // check if background loading is done
-    int getLoadedTrackCount() const; // get number of tracks loaded so far
-    void shuffle();               // randomize order
-    void start();                 // begin playback
-    void skipToNextTrack();       // advance to the next music track
-    void toggleMute();
+    // Additional IAudioSystem methods (forwarded to concrete implementation)
+    bool init() override;
+    void shutdown() override;
+    void addTrack(const std::string& path) override;
+    void addTrackAsync(const std::string& path) override;
+    void startBackgroundLoading() override;
+    bool isLoadingComplete() const override;
+    int getLoadedTrackCount() const override;
+    void start() override;
+    void skipToNextTrack() override;
+    void shuffle() override;
+    void toggleMute() override;
+    bool isMuted() const override;
     void setMuted(bool m);
-    bool isMuted() const { return muted; }
-    
-    // Menu music support
-    void setMenuTrack(const std::string& path);
-    void playMenuMusic();
-    void playGameMusic();
-    
-    // Queue a sound effect to mix over the music (pcm can be mono/stereo, any rate; will be converted)
-    void playSfx(const std::vector<int16_t>& pcm, int channels, int rate, float volume);
-    void shutdown();
+    void setMenuTrack(const std::string& path) override;
+    void playMenuMusic() override;
+    void playGameMusic() override;
+    void playSfx(const std::vector<int16_t>& pcm, int channels, int rate, float volume) override;
+
+    // Existing Audio class helper methods
+    void waitForLoadingComplete(); // wait for all tracks to finish loading
 private:
     Audio()=default; ~Audio()=default; Audio(const Audio&)=delete; Audio& operator=(const Audio&)=delete;
     static void SDLCALL streamCallback(void* userdata, SDL_AudioStream* stream, int additional, int total);
diff --git a/src/audio/AudioManager.cpp b/src/audio/AudioManager.cpp
new file mode 100644
index 0000000..775a4d2
--- /dev/null
+++ b/src/audio/AudioManager.cpp
@@ -0,0 +1,15 @@
+#include "AudioManager.h"
+#include "Audio.h"
+
+static IAudioSystem* g_audioSystem = nullptr;
+
+IAudioSystem* AudioManager::get() {
+    if (!g_audioSystem) {
+        g_audioSystem = &Audio::instance();
+    }
+    return g_audioSystem;
+}
+
+void AudioManager::set(IAudioSystem* sys) {
+    g_audioSystem = sys;
+}
diff --git a/src/audio/AudioManager.h b/src/audio/AudioManager.h
new file mode 100644
index 0000000..ebf078b
--- /dev/null
+++ b/src/audio/AudioManager.h
@@ -0,0 +1,11 @@
+#pragma once
+
+#include "../core/interfaces/IAudioSystem.h"
+
+class AudioManager {
+public:
+    // Get the currently registered audio system (may return Audio::instance())
+    static IAudioSystem* get();
+    // Replace the audio system (for tests or different backends)
+    static void set(IAudioSystem* sys);
+};
diff --git a/src/audio/SoundEffect.cpp b/src/audio/SoundEffect.cpp
index ecc34ee..e48393e 100644
--- a/src/audio/SoundEffect.cpp
+++ b/src/audio/SoundEffect.cpp
@@ -2,6 +2,7 @@
 #include "SoundEffect.h"
 #include <SDL3/SDL.h>
 #include "audio/Audio.h"
+#include "audio/AudioManager.h"
 #include <cstdio>
 #include <algorithm>
 #include <random>
@@ -93,7 +94,9 @@ void SimpleAudioPlayer::playSound(const std::vector<int16_t>& pcmData, int chann
         return;
     }
     // Route through shared Audio mixer so SFX always play over music
-    Audio::instance().playSfx(pcmData, channels, sampleRate, volume);
+    if (auto sys = AudioManager::get()) {
+        sys->playSfx(pcmData, channels, sampleRate, volume);
+    }
 }
 
 bool SoundEffect::loadWAV(const std::string& filePath) {
diff --git a/src/core/application/ApplicationManager.cpp b/src/core/application/ApplicationManager.cpp
index 9e4da60..e7c13e2 100644
--- a/src/core/application/ApplicationManager.cpp
+++ b/src/core/application/ApplicationManager.cpp
@@ -7,6 +7,7 @@
 #include "../interfaces/IInputHandler.h"
 #include <filesystem>
 #include "../../audio/Audio.h"
+#include "../../audio/AudioManager.h"
 #include "../../audio/SoundEffect.h"
 #include "../../persistence/Scores.h"
 #include "../../states/State.h"
@@ -267,7 +268,7 @@ void ApplicationManager::shutdown() {
     m_running = false;
 
     // Stop audio systems before tearing down SDL to avoid aborts/asserts
-    Audio::instance().shutdown();
+    if (auto sys = ::AudioManager::get()) sys->shutdown();
     SoundEffectManager::instance().shutdown();
 
     // Cleanup in reverse order of initialization
@@ -381,11 +382,11 @@ bool ApplicationManager::initializeManagers() {
 
                 // M: Toggle/mute music; start playback if unmuting and not started yet
                 if (!consume && sc == SDL_SCANCODE_M) {
-                    Audio::instance().toggleMute();
+                    if (auto sys = ::AudioManager::get()) sys->toggleMute();
                     m_musicEnabled = !m_musicEnabled;
-                    if (m_musicEnabled && !m_musicStarted && Audio::instance().getLoadedTrackCount() > 0) {
-                        Audio::instance().shuffle();
-                        Audio::instance().start();
+                    if (m_musicEnabled && !m_musicStarted && ::AudioManager::get() && ::AudioManager::get()->getLoadedTrackCount() > 0) {
+                        ::AudioManager::get()->shuffle();
+                        ::AudioManager::get()->start();
                         m_musicStarted = true;
                     }
                     consume = true;
@@ -393,11 +394,7 @@ bool ApplicationManager::initializeManagers() {
 
                 // N: Skip to next song in the playlist (or restart menu track)
                 if (!consume && sc == SDL_SCANCODE_N) {
-                    Audio::instance().skipToNextTrack();
-                    if (!m_musicStarted && Audio::instance().getLoadedTrackCount() > 0) {
-                        m_musicStarted = true;
-                        m_musicEnabled = true;
-                    }
+                    if (auto sys = ::AudioManager::get()) { sys->skipToNextTrack(); if (!m_musicStarted && sys->getLoadedTrackCount() > 0) { m_musicStarted = true; m_musicEnabled = true; } }
                     consume = true;
                 }
 
@@ -515,13 +512,13 @@ void ApplicationManager::registerServices() {
         SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION, "Registered IInputHandler service");
     }
     
-    // Register Audio system singleton
-    auto& audioInstance = Audio::instance();
-    auto audioPtr = std::shared_ptr<Audio>(&audioInstance, [](Audio*) {
-        // Custom deleter that does nothing since Audio is a singleton
-    });
-    m_serviceContainer.registerSingleton<IAudioSystem>(audioPtr);
-    SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION, "Registered IAudioSystem service");
+    // Register Audio system singleton (via AudioManager)
+    IAudioSystem* audioInstance = AudioManager::get();
+    if (audioInstance) {
+        std::shared_ptr<IAudioSystem> audioPtr(audioInstance, [](IAudioSystem*){});
+        m_serviceContainer.registerSingleton<IAudioSystem>(audioPtr);
+        SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION, "Registered IAudioSystem service");
+    }
     
     SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION, "Service registration completed successfully");
 }
@@ -618,7 +615,7 @@ bool ApplicationManager::initializeGame() {
     // as lambdas that reference members here.
 
     // Start background music loading similar to main.cpp: Audio init + file discovery
-    Audio::instance().init();
+    if (auto sys = ::AudioManager::get()) sys->init();
     // Discover available tracks (up to 100) and queue for background loading
     m_totalTracks = 0;
     std::vector<std::string> trackPaths;
@@ -634,15 +631,15 @@ bool ApplicationManager::initializeGame() {
     }
     m_totalTracks = static_cast<int>(trackPaths.size());
     for (const auto& path : trackPaths) {
-        Audio::instance().addTrackAsync(path);
+        if (auto sys = ::AudioManager::get()) sys->addTrackAsync(path);
     }
     if (m_totalTracks > 0) {
-        Audio::instance().startBackgroundLoading();
-    // Kick off playback now; Audio will pick a track once decoded.
-    // Do not mark as started yet; we'll flip the flag once a track is actually loaded.
-    if (m_musicEnabled) {
-            Audio::instance().shuffle();
-            Audio::instance().start();
+        if (auto sys = ::AudioManager::get()) sys->startBackgroundLoading();
+        // Kick off playback now; Audio will pick a track once decoded.
+        // Do not mark as started yet; we'll flip the flag once a track is actually loaded.
+        if (m_musicEnabled) {
+            if (auto sys = ::AudioManager::get()) { sys->shuffle(); sys->start(); }
+            m_musicStarted = true;
         }
         m_currentTrackLoading = 1; // mark started
     }
@@ -941,15 +938,15 @@ void ApplicationManager::setupStateHandlers() {
             // Start music as soon as at least one track has decoded (don’t wait for all)
                 // Start music as soon as at least one track has decoded (don't wait for all)
             if (m_musicEnabled && !m_musicStarted) {
-                if (Audio::instance().getLoadedTrackCount() > 0) {
-                    Audio::instance().shuffle();
-                    Audio::instance().start();
-                    m_musicStarted = true;
+                if (auto sys = ::AudioManager::get()) {
+                    if (sys->getLoadedTrackCount() > 0) { sys->shuffle(); sys->start(); m_musicStarted = true; }
                 }
             }
             // Track completion status for UI
-            if (!m_musicLoaded && Audio::instance().isLoadingComplete()) {
-                m_musicLoaded = true;
+            if (!m_musicLoaded) {
+                if (auto sys = ::AudioManager::get()) {
+                    if (sys->isLoadingComplete()) m_musicLoaded = true;
+                }
             }
         });
 
diff --git a/src/core/assets/AssetManager.cpp b/src/core/assets/AssetManager.cpp
index fbbba17..1aed990 100644
--- a/src/core/assets/AssetManager.cpp
+++ b/src/core/assets/AssetManager.cpp
@@ -1,6 +1,7 @@
 #include "AssetManager.h"
 #include "../../graphics/ui/Font.h"
 #include "../../audio/Audio.h"
+#include "../../audio/AudioManager.h"
 #include "../../audio/SoundEffect.h"
 #include <SDL3/SDL.h>
 #include <SDL3_image/SDL_image.h>
@@ -40,7 +41,7 @@ bool AssetManager::initialize(SDL_Renderer* renderer) {
     m_renderer = renderer;
     
     // Get references to singleton systems
-    m_audioSystem = &Audio::instance();
+    m_audioSystem = ::AudioManager::get();
     m_soundSystem = &SoundEffectManager::instance();
 
     m_initialized = true;
diff --git a/src/core/assets/AssetManager.h b/src/core/assets/AssetManager.h
index fbec918..aebf67b 100644
--- a/src/core/assets/AssetManager.h
+++ b/src/core/assets/AssetManager.h
@@ -7,12 +7,12 @@
 #include <memory>
 #include <functional>
 #include "../interfaces/IAssetLoader.h"
-#include "../interfaces/IAssetLoader.h"
 
 // Forward declarations
 class FontAtlas;
 class Audio;
 class SoundEffectManager;
+class IAudioSystem;
 
 /**
  * AssetManager - Centralized resource management following SOLID principles
@@ -121,7 +121,7 @@ private:
 
     // System references
     SDL_Renderer* m_renderer;
-    Audio* m_audioSystem;              // Pointer to singleton
+    IAudioSystem* m_audioSystem;              // Pointer to audio system (IAudioSystem)
     SoundEffectManager* m_soundSystem; // Pointer to singleton
 
     // Configuration
diff --git a/src/core/interfaces/IAudioSystem.h b/src/core/interfaces/IAudioSystem.h
index 4e4ac95..57e974e 100644
--- a/src/core/interfaces/IAudioSystem.h
+++ b/src/core/interfaces/IAudioSystem.h
@@ -1,6 +1,8 @@
 #pragma once
 
 #include <string>
+#include <vector>
+#include <cstdint>
 
 /**
  * @brief Abstract interface for audio system operations
@@ -52,4 +54,28 @@ public:
      * @return true if music is playing, false otherwise
      */
     virtual bool isMusicPlaying() const = 0;
+
+    // Extended control methods used by the application
+    virtual bool init() = 0;
+    virtual void shutdown() = 0;
+
+    virtual void addTrack(const std::string& path) = 0;
+    virtual void addTrackAsync(const std::string& path) = 0;
+    virtual void startBackgroundLoading() = 0;
+    virtual bool isLoadingComplete() const = 0;
+    virtual int getLoadedTrackCount() const = 0;
+
+    virtual void start() = 0;
+    virtual void skipToNextTrack() = 0;
+    virtual void shuffle() = 0;
+
+    virtual void toggleMute() = 0;
+    virtual bool isMuted() const = 0;
+
+    virtual void setMenuTrack(const std::string& path) = 0;
+    virtual void playMenuMusic() = 0;
+    virtual void playGameMusic() = 0;
+
+    // Low-level SFX path (raw PCM) used by internal SFX mixer
+    virtual void playSfx(const std::vector<int16_t>& pcm, int channels, int rate, float volume) = 0;
 };
diff --git a/src/gameplay/LineEffect.cpp b/src/gameplay/LineEffect.cpp
index 250ab05..944e316 100644
--- a/src/gameplay/LineEffect.cpp
+++ b/src/gameplay/LineEffect.cpp
@@ -3,6 +3,7 @@
 #include <algorithm>
 #include <cmath>
 #include "audio/Audio.h"
+#include "audio/AudioManager.h"
 
 #ifndef M_PI
 #define M_PI 3.14159265358979323846
@@ -266,6 +267,6 @@ void LineEffect::playLineClearSound(int lineCount) {
     const std::vector<int16_t>* sample = (lineCount == 4) ? &tetrisSample : &lineClearSample;
     if (sample && !sample->empty()) {
         // Mix via shared Audio device so it layers with music
-        Audio::instance().playSfx(*sample, 2, 44100, (lineCount == 4) ? 0.9f : 0.7f);
+        if (auto sys = ::AudioManager::get()) sys->playSfx(*sample, 2, 44100, (lineCount == 4) ? 0.9f : 0.7f);
     }
 }
diff --git a/src/gameplay/effects/LineEffect.cpp b/src/gameplay/effects/LineEffect.cpp
index 713718d..5d9d67b 100644
--- a/src/gameplay/effects/LineEffect.cpp
+++ b/src/gameplay/effects/LineEffect.cpp
@@ -3,6 +3,7 @@
 #include <algorithm>
 #include <cmath>
 #include "audio/Audio.h"
+#include "audio/AudioManager.h"
 #include "gameplay/core/Game.h"
 
 #ifndef M_PI
@@ -461,7 +462,7 @@ void LineEffect::playLineClearSound(int lineCount) {
     const std::vector<int16_t>* sample = (lineCount == 4) ? &tetrisSample : &lineClearSample;
     if (sample && !sample->empty()) {
         // Mix via shared Audio device so it layers with music
-        Audio::instance().playSfx(*sample, 2, 44100, (lineCount == 4) ? 0.9f : 0.7f);
+        if (auto sys = ::AudioManager::get()) sys->playSfx(*sample, 2, 44100, (lineCount == 4) ? 0.9f : 0.7f);
     }
 }
 
diff --git a/src/states/MenuState.cpp b/src/states/MenuState.cpp
index 3b9bcb1..86d3d3f 100644
--- a/src/states/MenuState.cpp
+++ b/src/states/MenuState.cpp
@@ -8,6 +8,7 @@
 #include "../core/Settings.h"
 #include "../core/state/StateManager.h"
 #include "../audio/Audio.h"
+#include "../audio/AudioManager.h"
 #include "../audio/SoundEffect.h"
 #include <SDL3/SDL.h>
 #include <SDL3/SDL_render.h>
@@ -180,7 +181,7 @@ void MenuState::showCoopSetupPanel(bool show, bool resumeMusic) {
             coopSetupStep = CoopSetupStep::ChoosePartner;
             // Resume menu music only when requested (ESC should pass resumeMusic=false)
             if (resumeMusic && ctx.musicEnabled && *ctx.musicEnabled) {
-                Audio::instance().playMenuMusic();
+                if (auto sys = ::AudioManager::get()) sys->playMenuMusic();
             }
         }
     }
diff --git a/src/states/OptionsState.cpp b/src/states/OptionsState.cpp
index bec188d..feb82db 100644
--- a/src/states/OptionsState.cpp
+++ b/src/states/OptionsState.cpp
@@ -2,6 +2,7 @@
 #include "../core/state/StateManager.h"
 #include "../graphics/ui/Font.h"
 #include "../audio/Audio.h"
+#include "../audio/AudioManager.h"
 #include "../audio/SoundEffect.h"
 #include <SDL3/SDL.h>
 #include <algorithm>
@@ -220,7 +221,7 @@ void OptionsState::toggleFullscreen() {
 }
 
 void OptionsState::toggleMusic() {
-    Audio::instance().toggleMute();
+    if (auto sys = ::AudioManager::get()) sys->toggleMute();
     // If muted, music is disabled. If not muted, music is enabled.
     // Note: Audio::instance().isMuted() returns true if muted.
     // But Audio class doesn't expose isMuted directly in header usually?
diff --git a/src/states/VideoState.cpp b/src/states/VideoState.cpp
index 10360dc..6602390 100644
--- a/src/states/VideoState.cpp
+++ b/src/states/VideoState.cpp
@@ -3,6 +3,7 @@
 
 #include "../video/VideoPlayer.h"
 #include "../audio/Audio.h"
+#include "../audio/AudioManager.h"
 #include "../core/state/StateManager.h"
 
 #include <SDL3/SDL.h>
@@ -104,7 +105,7 @@ void VideoState::startAudioIfReady() {
     if (m_audioPcm.empty()) return;
 
     // Use the existing audio output path (same device as music/SFX).
-    Audio::instance().playSfx(m_audioPcm, m_audioChannels, m_audioRate, 1.0f);
+    if (auto sys = ::AudioManager::get()) sys->playSfx(m_audioPcm, m_audioChannels, m_audioRate, 1.0f);
     m_audioStarted = true;
 }