diff --git a/assets/sfx/confirm.mp3 b/assets/sfx/confirm.mp3
deleted file mode 100644
index 7cfc0a8..0000000
Binary files a/assets/sfx/confirm.mp3 and /dev/null differ
diff --git a/assets/sfx/correct.wav b/assets/sfx/correct.wav
new file mode 100644
index 0000000..604564f
Binary files /dev/null and b/assets/sfx/correct.wav differ
diff --git a/assets/sfx/incorrect.wav b/assets/sfx/incorrect.wav
new file mode 100644
index 0000000..79ac2c6
Binary files /dev/null and b/assets/sfx/incorrect.wav differ
diff --git a/lib/src/screens/browse_screen.dart b/lib/src/screens/browse_screen.dart
index 51d7d53..bfcf510 100644
--- a/lib/src/screens/browse_screen.dart
+++ b/lib/src/screens/browse_screen.dart
@@ -868,8 +868,9 @@ class _BrowseScreenState extends State<BrowseScreen>
 
 class _VocabDetailsDialog extends StatefulWidget {
   final VocabularyItem vocab;
+  final ThemeData theme;
 
-  const _VocabDetailsDialog({required this.vocab});
+  const _VocabDetailsDialog({required this.vocab, required this.theme});
 
   @override
   State<_VocabDetailsDialog> createState() => _VocabDetailsDialogState();
@@ -881,10 +882,10 @@ class _VocabDetailsDialogState extends State<_VocabDetailsDialog> {
   @override
   void initState() {
     super.initState();
-    _fetchExampleSentences(context);
+    _fetchExampleSentences();
   }
 
-  Future<void> _fetchExampleSentences(BuildContext context) async {
+  Future<void> _fetchExampleSentences() async {
     try {
       final uri = Uri.parse(
         'https://jisho.org/api/v1/search/words?keyword=${Uri.encodeComponent(widget.vocab.characters)}',
@@ -911,11 +912,11 @@ class _VocabDetailsDialogState extends State<_VocabDetailsDialog> {
                     children: [
                       Text(
                         japaneseWord,
-                        style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+                        style: TextStyle(color: widget.theme.colorScheme.onSurface),
                       ),
                       Text(
                         englishDefinition,
-                        style: TextStyle(color: Theme.of(context).colorScheme.onSurfaceVariant),
+                        style: TextStyle(color: widget.theme.colorScheme.onSurfaceVariant),
                       ),
                       const SizedBox(height: 8),
                     ],
@@ -929,7 +930,7 @@ class _VocabDetailsDialogState extends State<_VocabDetailsDialog> {
           sentences.add(
             Text(
               'No example sentences found.',
-              style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+              style: TextStyle(color: widget.theme.colorScheme.onSurface),
             ),
           );
         }
@@ -944,7 +945,7 @@ class _VocabDetailsDialogState extends State<_VocabDetailsDialog> {
             _exampleSentences = [
               Text(
                 'Failed to load example sentences.',
-                style: TextStyle(color: Theme.of(context).colorScheme.error),
+                style: TextStyle(color: widget.theme.colorScheme.error),
               ),
             ];
           });
@@ -956,7 +957,7 @@ class _VocabDetailsDialogState extends State<_VocabDetailsDialog> {
           _exampleSentences = [
             Text(
               'Error loading example sentences.',
-              style: TextStyle(color: Theme.of(context).colorScheme.error),
+              style: TextStyle(color: widget.theme.colorScheme.error),
             ),
           ];
         });
@@ -992,39 +993,39 @@ class _VocabDetailsDialogState extends State<_VocabDetailsDialog> {
         children: [
           Text(
             'Level: ${widget.vocab.level}',
-            style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+            style: TextStyle(color: widget.theme.colorScheme.onSurface),
           ),
           const SizedBox(height: 16),
           if (widget.vocab.meanings.isNotEmpty)
             Text(
               'Meanings: ${widget.vocab.meanings.join(', ')}',
-              style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+              style: TextStyle(color: widget.theme.colorScheme.onSurface),
             ),
           const SizedBox(height: 16),
           if (widget.vocab.readings.isNotEmpty)
             Text(
               'Readings: ${widget.vocab.readings.join(', ')}',
-              style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+              style: TextStyle(color: widget.theme.colorScheme.onSurface),
             ),
           const SizedBox(height: 16),
-          Divider(color: Theme.of(context).colorScheme.onSurfaceVariant),
+          Divider(color: widget.theme.colorScheme.onSurfaceVariant),
           const SizedBox(height: 16),
           Text(
             'SRS Scores:',
-            style: TextStyle(color: Theme.of(context).colorScheme.onSurface, fontWeight: FontWeight.bold),
+            style: TextStyle(color: widget.theme.colorScheme.onSurface, fontWeight: FontWeight.bold),
           ),
           ...srsScores.entries.map(
             (entry) => Text(
               '  ${entry.key}: ${entry.value}',
-              style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+              style: TextStyle(color: widget.theme.colorScheme.onSurface),
             ),
           ),
           const SizedBox(height: 16),
-          Divider(color: Theme.of(context).colorScheme.onSurfaceVariant),
+          Divider(color: widget.theme.colorScheme.onSurfaceVariant),
           const SizedBox(height: 16),
           Text(
             'Example Sentences:',
-            style: TextStyle(color: Theme.of(context).colorScheme.onSurface, fontWeight: FontWeight.bold),
+            style: TextStyle(color: widget.theme.colorScheme.onSurface, fontWeight: FontWeight.bold),
           ),
           ..._exampleSentences,
         ],
@@ -1034,22 +1035,23 @@ class _VocabDetailsDialogState extends State<_VocabDetailsDialog> {
 }
 
 void _showVocabDetailsDialog(BuildContext context, VocabularyItem vocab) {
+  final currentTheme = Theme.of(context);
   showDialog(
     context: context,
     builder: (dialogContext) {
       return AlertDialog(
-        backgroundColor: Theme.of(context).colorScheme.surfaceContainer,
+        backgroundColor: currentTheme.colorScheme.surfaceContainer,
         title: Text(
           'Details for ${vocab.characters}',
-          style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+          style: TextStyle(color: currentTheme.colorScheme.onSurface),
         ),
-        content: _VocabDetailsDialog(vocab: vocab),
+        content: _VocabDetailsDialog(vocab: vocab, theme: currentTheme),
         actions: [
           TextButton(
             onPressed: () => Navigator.of(dialogContext).pop(),
             child: Text(
               'Close',
-              style: TextStyle(color: Theme.of(context).colorScheme.primary),
+              style: TextStyle(color: currentTheme.colorScheme.primary),
             ),
           ),
         ],
diff --git a/lib/src/screens/custom_quiz_screen.dart b/lib/src/screens/custom_quiz_screen.dart
index 44f6d55..306dbad 100644
--- a/lib/src/screens/custom_quiz_screen.dart
+++ b/lib/src/screens/custom_quiz_screen.dart
@@ -5,6 +5,8 @@ import '../widgets/options_grid.dart';
 import '../widgets/kanji_card.dart';
 import 'package:provider/provider.dart';
 import '../services/tts_service.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+import 'package:audioplayers/audioplayers.dart';
 
 enum CustomQuizMode {
   japaneseToEnglish,
@@ -42,6 +44,11 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
   late AnimationController _shakeController;
   late Animation<double> _shakeAnimation;
   final List<String> _incorrectlyAnsweredItems = [];
+  final _audioPlayer = AudioPlayer();
+
+  bool _playIncorrectSound = true;
+  bool _playCorrectSound = true;
+  bool _playNarrator = true;
 
   @override
   void initState() {
@@ -58,6 +65,16 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
     _shakeAnimation = Tween<double>(begin: 0, end: 1).animate(
       CurvedAnimation(parent: _shakeController, curve: Curves.elasticIn),
     );
+    _loadSettings();
+  }
+
+  Future<void> _loadSettings() async {
+    final prefs = await SharedPreferences.getInstance();
+    setState(() {
+      _playIncorrectSound = prefs.getBool('playIncorrectSound') ?? true;
+      _playCorrectSound = prefs.getBool('playCorrectSound') ?? true;
+      _playNarrator = prefs.getBool('playNarrator') ?? true;
+    });
   }
 
   @override
@@ -88,7 +105,7 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
 
   void playAudio() async {
     if (widget.quizMode == CustomQuizMode.listeningComprehension &&
-        _currentIndex < _shuffledDeck.length) {
+        _currentIndex < _shuffledDeck.length && _playNarrator) {
       final ttsService = Provider.of<TtsService>(context, listen: false);
       await ttsService.speak(_shuffledDeck[_currentIndex].characters);
     }
@@ -143,8 +160,8 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
         : currentItem.meaning;
     final isCorrect = answer == correctAnswer;
 
+    int currentSrsLevel = 0; // Initialize with a default value
     if (currentItem.useInterval) {
-      int currentSrsLevel;
       switch (widget.quizMode) {
         case CustomQuizMode.japaneseToEnglish:
           currentSrsLevel = currentItem.srsData.japaneseToEnglish;
@@ -234,12 +251,55 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
     }
 
     if (isCorrect) {
-      if (widget.quizMode == CustomQuizMode.japaneseToEnglish ||
-          widget.quizMode == CustomQuizMode.englishToJapanese) {
-        await _speak(currentItem.characters);
+      if (_incorrectlyAnsweredItems.contains(currentItem.characters)) {
+        _incorrectlyAnsweredItems.remove(currentItem.characters);
+      } else {
+        currentSrsLevel++;
+      }
+      final interval = pow(2, currentSrsLevel).toInt();
+      final newNextReview = DateTime.now().add(Duration(hours: interval));
+      switch (widget.quizMode) {
+        case CustomQuizMode.japaneseToEnglish:
+          currentItem.srsData.japaneseToEnglishNextReview = newNextReview;
+          break;
+        case CustomQuizMode.englishToJapanese:
+          currentItem.srsData.englishToJapaneseNextReview = newNextReview;
+          break;
+        case CustomQuizMode.listeningComprehension:
+          currentItem.srsData.listeningComprehensionNextReview =
+              newNextReview;
+          break;
+      }
+      if (_playCorrectSound && !_playNarrator) {
+        await _audioPlayer.play(AssetSource('sfx/correct.wav'));
+      } else if (_playNarrator) {
+        if (widget.quizMode == CustomQuizMode.japaneseToEnglish ||
+            widget.quizMode == CustomQuizMode.englishToJapanese) {
+          await _speak(currentItem.characters);
+        }
       }
       await Future.delayed(const Duration(milliseconds: 500));
     } else {
+      if (!_incorrectlyAnsweredItems.contains(currentItem.characters)) {
+        _incorrectlyAnsweredItems.add(currentItem.characters);
+      }
+      currentSrsLevel = max(0, currentSrsLevel - 1);
+      final newNextReview = DateTime.now().add(const Duration(hours: 1));
+      switch (widget.quizMode) {
+        case CustomQuizMode.japaneseToEnglish:
+          currentItem.srsData.japaneseToEnglishNextReview = newNextReview;
+          break;
+        case CustomQuizMode.englishToJapanese:
+          currentItem.srsData.englishToJapaneseNextReview = newNextReview;
+          break;
+        case CustomQuizMode.listeningComprehension:
+          currentItem.srsData.listeningComprehensionNextReview =
+              newNextReview;
+          break;
+      }
+      if (_playIncorrectSound) {
+        await _audioPlayer.play(AssetSource('sfx/incorrect.wav'));
+      }
       _shakeController.forward(from: 0);
       await Future.delayed(const Duration(milliseconds: 900));
     }
diff --git a/lib/src/screens/home_screen.dart b/lib/src/screens/home_screen.dart
index ce16ec2..17c2fe9 100644
--- a/lib/src/screens/home_screen.dart
+++ b/lib/src/screens/home_screen.dart
@@ -54,6 +54,7 @@ class _HomeScreenState extends State<HomeScreen>
   final _quizStates = [_QuizState(), _QuizState(), _QuizState()];
   _QuizState get _currentQuizState => _quizStates[_tabController.index];
 
+  bool _playIncorrectSound = true;
   bool _playCorrectSound = true;
   bool _apiKeyMissing = false;
 
@@ -78,6 +79,7 @@ class _HomeScreenState extends State<HomeScreen>
   Future<void> _loadSettings() async {
     final prefs = await SharedPreferences.getInstance();
     setState(() {
+      _playIncorrectSound = prefs.getBool('playIncorrectSound') ?? true;
       _playCorrectSound = prefs.getBool('playCorrectSound') ?? true;
     });
   }
@@ -311,10 +313,13 @@ class _HomeScreenState extends State<HomeScreen>
       quizState.score += 1;
       srsItemForUpdate.srsStage += 1;
       if (_playCorrectSound) {
-        _audioPlayer.play(AssetSource('sfx/confirm.mp3'));
+        _audioPlayer.play(AssetSource('sfx/correct.wav'));
       }
     } else {
       srsItemForUpdate.srsStage = max(0, srsItemForUpdate.srsStage - 1);
+      if (_playIncorrectSound) {
+        _audioPlayer.play(AssetSource('sfx/incorrect.wav'));
+      }
     }
     srsItemForUpdate.lastAsked = DateTime.now();
     current.srsItems[srsKey] = srsItemForUpdate;
diff --git a/lib/src/screens/settings_screen.dart b/lib/src/screens/settings_screen.dart
index 25b85e7..c474711 100644
--- a/lib/src/screens/settings_screen.dart
+++ b/lib/src/screens/settings_screen.dart
@@ -15,8 +15,9 @@ class SettingsScreen extends StatefulWidget {
 
 class _SettingsScreenState extends State<SettingsScreen> {
   final TextEditingController _apiKeyController = TextEditingController();
-  bool _playAudio = true;
+  bool _playIncorrectSound = true;
   bool _playCorrectSound = true;
+  bool _playNarrator = true;
 
   @override
   void dispose() {
@@ -39,8 +40,9 @@ class _SettingsScreenState extends State<SettingsScreen> {
   Future<void> _loadSettings() async {
     final prefs = await SharedPreferences.getInstance();
     setState(() {
-      _playAudio = prefs.getBool('playAudio') ?? true;
+      _playIncorrectSound = prefs.getBool('playIncorrectSound') ?? true;
       _playCorrectSound = prefs.getBool('playCorrectSound') ?? true;
+      _playNarrator = prefs.getBool('playNarrator') ?? true;
     });
   }
 
@@ -108,17 +110,17 @@ class _SettingsScreenState extends State<SettingsScreen> {
             const SizedBox(height: 24),
             SwitchListTile(
               title: Text(
-                'Play audio for vocabulary',
+                'Play incorrect sound',
                 style: TextStyle(
                   color: Theme.of(context).colorScheme.onSurface,
                 ),
               ),
-              value: _playAudio,
+              value: _playIncorrectSound,
               onChanged: (value) async {
                 final prefs = await SharedPreferences.getInstance();
-                prefs.setBool('playAudio', value);
+                prefs.setBool('playIncorrectSound', value);
                 setState(() {
-                  _playAudio = value;
+                  _playIncorrectSound = value;
                 });
               },
               activeThumbColor: Theme.of(context).colorScheme.primary,
@@ -133,7 +135,7 @@ class _SettingsScreenState extends State<SettingsScreen> {
             const SizedBox(height: 12),
             SwitchListTile(
               title: Text(
-                'Play sound on correct answer',
+                'Play correct sound',
                 style: TextStyle(
                   color: Theme.of(context).colorScheme.onSurface,
                 ),
@@ -156,6 +158,31 @@ class _SettingsScreenState extends State<SettingsScreen> {
               ),
             ),
             const SizedBox(height: 12),
+            SwitchListTile(
+              title: Text(
+                'Play narrator (TTS)',
+                style: TextStyle(
+                  color: Theme.of(context).colorScheme.onSurface,
+                ),
+              ),
+              value: _playNarrator,
+              onChanged: (value) async {
+                final prefs = await SharedPreferences.getInstance();
+                prefs.setBool('playNarrator', value);
+                setState(() {
+                  _playNarrator = value;
+                });
+              },
+              activeThumbColor: Theme.of(context).colorScheme.primary,
+              inactiveThumbColor: Theme.of(
+                context,
+              ).colorScheme.onSurfaceVariant,
+              tileColor: Theme.of(context).colorScheme.surfaceContainer,
+              shape: RoundedRectangleBorder(
+                borderRadius: BorderRadius.circular(6),
+              ),
+            ),
+            const SizedBox(height: 12),
             ListTile(
               title: Text(
                 'Theme',
diff --git a/lib/src/screens/vocab_screen.dart b/lib/src/screens/vocab_screen.dart
index 9ed43c1..c120f22 100644
--- a/lib/src/screens/vocab_screen.dart
+++ b/lib/src/screens/vocab_screen.dart
@@ -45,8 +45,9 @@ class _VocabScreenState extends State<VocabScreen>
   final _quizStates = [_QuizState(), _QuizState(), _QuizState()];
   _QuizState get _currentQuizState => _quizStates[_tabController.index];
 
-  bool _playAudio = true;
+  bool _playIncorrectSound = true;
   bool _playCorrectSound = true;
+  bool _playNarrator = true;
   bool _apiKeyMissing = false;
 
   @override
@@ -72,8 +73,9 @@ class _VocabScreenState extends State<VocabScreen>
   Future<void> _loadSettings() async {
     final prefs = await SharedPreferences.getInstance();
     setState(() {
-      _playAudio = prefs.getBool('playAudio') ?? true;
+      _playIncorrectSound = prefs.getBool('playIncorrectSound') ?? true;
       _playCorrectSound = prefs.getBool('playCorrectSound') ?? true;
+      _playNarrator = prefs.getBool('playNarrator') ?? true;
     });
   }
 
@@ -222,7 +224,7 @@ class _VocabScreenState extends State<VocabScreen>
     final current = _currentQuizState.current;
     if (current == null || current.pronunciationAudios.isEmpty) return;
 
-    if (playOnLoad && !_playAudio) return;
+    if (playOnLoad && !_playNarrator) return;
 
     final maleAudios = current.pronunciationAudios.where(
       (a) => a.gender == 'male',
@@ -263,6 +265,9 @@ class _VocabScreenState extends State<VocabScreen>
       srsItem.srsStage += 1;
     } else {
       srsItem.srsStage = max(0, srsItem.srsStage - 1);
+      if (_playIncorrectSound) {
+        await _audioPlayer.play(AssetSource('sfx/incorrect.wav'));
+      }
     }
     srsItem.lastAsked = DateTime.now();
     current.srsItems[srsKey] = srsItem;
@@ -294,10 +299,9 @@ class _VocabScreenState extends State<VocabScreen>
     ScaffoldMessenger.of(context).showSnackBar(snack);
 
     if (isCorrect) {
-      if (_playCorrectSound) {
-        await _audioPlayer.play(AssetSource('sfx/confirm.mp3'));
-      }
-      if (_playAudio) {
+      if (_playCorrectSound && !_playNarrator) {
+        await _audioPlayer.play(AssetSource('sfx/correct.wav'));
+      } else if (_playNarrator) {
         final maleAudios = current.pronunciationAudios.where(
           (a) => a.gender == 'male',
         );
diff --git a/pubspec.yaml b/pubspec.yaml
index 9193382..e13d084 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -34,4 +34,5 @@ flutter_icons:
 flutter:
   uses-material-design: true
   assets:
-    - assets/sfx/confirm.mp3
\ No newline at end of file
+    - assets/sfx/correct.wav
+    - assets/sfx/incorrect.wav
\ No newline at end of file