diff --git a/assets/music/background.mp3 b/assets/music/background.mp3
new file mode 100644
index 0000000..e8899f9
Binary files /dev/null and b/assets/music/background.mp3 differ
diff --git a/assets/music/background.wav b/assets/music/background.wav
deleted file mode 100644
index 900ec90..0000000
Binary files a/assets/music/background.wav and /dev/null differ
diff --git a/settings.toml b/settings.toml
index ccda425..30f1608 100644
--- a/settings.toml
+++ b/settings.toml
@@ -1,5 +1,5 @@
 [General]
-pause = ["esc", "F1"]
+pause = ["escape", "F1"] # WIP
 quit = ["q"]
 
 [Movement]
@@ -18,7 +18,7 @@ ccw = [
 ] # counter-clockwise
 
 [Action]
-hold = ["shift", "c", "keypad 0"]
+hold = ["left shift", "right shift", "c", "keypad 0"] # WIP
 drop = ["space", "keypad 5"]
 
 [Volume.Music]
diff --git a/src/game/screens/game.py b/src/game/screens/game.py
index 371001f..9a9667c 100644
--- a/src/game/screens/game.py
+++ b/src/game/screens/game.py
@@ -30,6 +30,7 @@ class Game(BaseScreen):
     def __init__(self, game_mode: GameMode, settings: dict[str, Any]) -> None:
         self.game_mode = game_mode
         self.settings = settings
+        self.paused = False
         self._initialize_game_components()
         self._start_background_music()
 
diff --git a/src/game/screens/tetris.py b/src/game/screens/tetris.py
index 3c4b02e..1972df0 100644
--- a/src/game/screens/tetris.py
+++ b/src/game/screens/tetris.py
@@ -69,7 +69,7 @@ class Tetris(BaseScreen):
         """Run a single iteration of the game loop."""
         self.draw()
         self._timer_update()
-        self.handle_event()
+        self.handle_events()
 
     def draw(self) -> None:
         """Draw the game surface and its components."""
@@ -83,7 +83,7 @@ class Tetris(BaseScreen):
         self._update_display_surface()
         self.sprites.update()
 
-    def handle_event(self) -> None:
+    def handle_events(self) -> None:
         """Handle player input events."""
         keys: pygame.key.ScancodeWrapper = pygame.key.get_pressed()
 
@@ -366,12 +366,12 @@ class Tetris(BaseScreen):
 
         See `settings.toml` for the default key bindings.
         """
-        right_keys = [
+        right_keys: list[int] = [
             pygame.key.key_code(key) for key in self.settings["Movement"]["right"]
         ]
         right_key_pressed = any(keys[key] for key in right_keys)
 
-        left_keys = [
+        left_keys: list[int] = [
             pygame.key.key_code(key) for key in self.settings["Movement"]["left"]
         ]
         left_key_pressed = any(keys[key] for key in left_keys)
@@ -390,10 +390,12 @@ class Tetris(BaseScreen):
 
         See `settings.toml` for the default key bindings.
         """
-        cw_keys = [pygame.key.key_code(key) for key in self.settings["Rotation"]["cw"]]
+        cw_keys: list[int] = [
+            pygame.key.key_code(key) for key in self.settings["Rotation"]["cw"]
+        ]
         cw_key_pressed = any(keys[key] for key in cw_keys)
 
-        ccw_keys = [
+        ccw_keys: list[int] = [
             pygame.key.key_code(key) for key in self.settings["Rotation"]["ccw"]
         ]
         ccw_key_pressed = any(keys[key] for key in ccw_keys)
@@ -413,7 +415,7 @@ class Tetris(BaseScreen):
 
         See `settings.toml` for the default key bindings.
         """
-        down_keys = [
+        down_keys: list[int] = [
             pygame.key.key_code(key) for key in self.settings["Movement"]["down"]
         ]
         down_key_pressed = any(keys[key] for key in down_keys)
diff --git a/src/utils/config.py b/src/utils/config.py
index 8ff77aa..169dd06 100644
--- a/src/utils/config.py
+++ b/src/utils/config.py
@@ -61,7 +61,7 @@ class Window:
 
 @define
 class Music:
-    background: Path = BASE_PATH / "assets" / "music" / "background.wav"
+    background: Path = BASE_PATH / "assets" / "music" / "background.mp3"
     landing: Path = BASE_PATH / "assets" / "music" / "landing.wav"