diff --git a/adhan-webapp/app.py b/adhan-webapp/app.py
index 2981ee5..3487221 100644
--- a/adhan-webapp/app.py
+++ b/adhan-webapp/app.py
@@ -6,6 +6,9 @@ from hijridate import Gregorian
 from functools import lru_cache
 import time
 from concurrent.futures import ThreadPoolExecutor
+import asyncio
+import aiohttp
+from functools import wraps
 
 app = Flask(__name__)
 
@@ -15,6 +18,12 @@ last_api_call = {}
 cached_data = {}
 executor = ThreadPoolExecutor(max_workers=3)  # Voor parallelle API calls
 
+def async_route(f):
+    @wraps(f)
+    def wrapped(*args, **kwargs):
+        return asyncio.run(f(*args, **kwargs))
+    return wrapped
+
 def get_cached_data(key, fetch_func, duration=CACHE_DURATION):
     """Haal data uit cache of voer fetch_func uit als cache verlopen is"""
     current_time = time.time()
@@ -28,14 +37,67 @@ def get_cached_data(key, fetch_func, duration=CACHE_DURATION):
     last_api_call[key] = current_time
     return data
 
-def fetch_data_parallel():
-    """Haal alle data parallel op"""
-    futures = {
-        'weather': executor.submit(fetch_weather_data),
-        'sonos': executor.submit(fetch_sonos_zones),
-        'date': executor.submit(get_date_info)
+async def fetch_weather_data_async():
+    """Asynchrone versie van weather data ophalen"""
+    try:
+        async with aiohttp.ClientSession() as session:
+            params = {
+                'q': WEATHER_LOCATION,
+                'appid': OPENWEATHER_API_KEY,
+                'units': 'metric',
+                'lang': 'nl'
+            }
+            async with session.get('https://api.openweathermap.org/data/2.5/weather', params=params, timeout=5) as response:
+                data = await response.json()
+                
+                weather_info = {
+                    'temperature': round(data['main']['temp']),
+                    'feels_like': round(data['main']['feels_like']),
+                    'description': data['weather'][0]['description'].capitalize(),
+                    'humidity': data['main']['humidity'],
+                    'wind_speed': round(data['wind']['speed'] * 3.6),
+                    'icon': data['weather'][0]['icon']
+                }
+                return weather_info
+    except Exception as e:
+        print(f"⚠️ Fout bij ophalen weerdata: {e}")
+        return {
+            'temperature': '--',
+            'feels_like': '--',
+            'description': 'Weer niet beschikbaar',
+            'humidity': '--',
+            'wind_speed': '--',
+            'icon': '01d'
+        }
+
+async def fetch_sonos_zones_async():
+    """Asynchrone versie van Sonos zones ophalen"""
+    try:
+        async with aiohttp.ClientSession() as session:
+            async with session.get(f'http://{SONOS_API_IP}:5005/zones', timeout=5) as response:
+                data = await response.json()
+                zones = []
+                for group in data:
+                    for player in group['members']:
+                        zones.append(player['roomName'])
+                return sorted(set(zones))
+    except Exception as e:
+        print(f'Fout bij ophalen Sonos-zones: {e}')
+        return ['Woonkamer', 'Slaapkamer', 'Keuken']
+
+async def fetch_data_parallel_async():
+    """Haal alle data parallel op met asyncio"""
+    weather_task = asyncio.create_task(fetch_weather_data_async())
+    sonos_task = asyncio.create_task(fetch_sonos_zones_async())
+    date_task = asyncio.create_task(asyncio.to_thread(get_date_info))
+    
+    weather, sonos, date = await asyncio.gather(weather_task, sonos_task, date_task)
+    
+    return {
+        'weather': weather,
+        'sonos': sonos,
+        'date': date
     }
-    return {key: future.result() for key, future in futures.items()}
 
 # Voeg cache-control headers toe voor statische bestanden
 @app.after_request
@@ -332,7 +394,8 @@ def index():
                            date_info=date_info)
 
 @app.route('/instellingen', methods=['GET', 'POST'])
-def instellingen():
+@async_route
+async def instellingen():
     if request.method == 'POST':
         try:
             # Nieuwe volume instellingen
@@ -409,9 +472,9 @@ def instellingen():
             print(f"❌ Fout bij opslaan instellingen: {e}")
             # Probeer alsnog door te gaan zonder de Pi volume instelling
             return redirect('/instellingen')
-
-    # Haal alle data parallel op
-    data = fetch_data_parallel()
+    
+    # Haal alle data parallel op met asyncio
+    data = await fetch_data_parallel_async()
     
     return render_template('settings.html',
                          settings=load_settings(),
diff --git a/adhan-webapp/done b/adhan-webapp/done
index 81119f5..d582ecc 100644
--- a/adhan-webapp/done
+++ b/adhan-webapp/done
@@ -15,3 +15,4 @@ Mon May 26 18:17:57 CEST 2025: Tijdzone probleem opgelost - Container gebruikt n
 Wed May 28 14:09:12 CEST 2025: Sonos debug tijd synchronisatie geïmplementeerd - get_current_volume functie en cron script gebruiken nu debug tijd API, volume bepaling werkt correct in debug mode
 2025-05-29 21:24:37 - Performance optimalisaties toegevoegd: caching voor API calls en instellingen
 2025-05-29 21:27:02 - UI optimalisaties toegevoegd: lazy loading, parallelle API calls en caching
+2025-05-29 21:30:24 - Geavanceerde optimalisaties toegevoegd: async/await, debouncing en DOM caching
diff --git a/adhan-webapp/templates/settings.html b/adhan-webapp/templates/settings.html
index 9c085d9..a3174e4 100644
--- a/adhan-webapp/templates/settings.html
+++ b/adhan-webapp/templates/settings.html
@@ -327,37 +327,134 @@
   </div>
 
   <script>
+    // Debounce functie voor betere performance
+    function debounce(func, wait) {
+      let timeout;
+      return function executedFunction(...args) {
+        const later = () => {
+          clearTimeout(timeout);
+          func(...args);
+        };
+        clearTimeout(timeout);
+        timeout = setTimeout(later, wait);
+      };
+    }
+
+    // Cache DOM elementen
+    const audioSelect = document.getElementById('audioSelect');
+    const previewAudio = document.getElementById('previewAudio');
+    const piVolumeSlider = document.getElementById('piVolumeSlider');
+    const volumeDisplay = document.getElementById('volumeDisplay');
+
     function previewAudio() {
-      const select = document.getElementById('audioSelect');
-      const audio = document.getElementById('previewAudio');
-      const selectedClip = select.value;
+      if (!previewAudio || !audioSelect) return;
       
-      audio.src = `/static/clips/${selectedClip}`;
-      audio.play().catch(e => {
+      const selectedClip = audioSelect.value;
+      previewAudio.src = `/static/clips/${selectedClip}`;
+      previewAudio.play().catch(e => {
         console.log('Audio afspelen mislukt:', e);
         alert('Kon audio niet afspelen. Controleer of het bestand bestaat.');
       });
     }
 
-    // Auto-update preview audio source when selection changes
-    document.getElementById('audioSelect').addEventListener('change', function() {
-      const audio = document.getElementById('previewAudio');
-      audio.src = `/static/clips/${this.value}`;
+    // Gebruik event delegation voor betere performance
+    document.addEventListener('change', function(e) {
+      if (e.target === audioSelect && previewAudio) {
+        previewAudio.src = `/static/clips/${e.target.value}`;
+      }
     });
 
-    // Set initial audio source
-    window.onload = function() {
-      const select = document.getElementById('audioSelect');
-      const audio = document.getElementById('previewAudio');
-      audio.src = `/static/clips/${select.value}`;
+    // Optimize volume updates
+    const updateVolumeDisplay = debounce(function(value) {
+      if (volumeDisplay) {
+        volumeDisplay.textContent = value + '%';
+      }
+    }, 100);
+
+    // Optimize Pi volume testing
+    const testPiVolume = debounce(function() {
+      if (!piVolumeSlider) return;
+      
+      const volume = piVolumeSlider.value;
+      
+      fetch('/api/set-pi-volume', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ volume: parseInt(volume) })
+      })
+      .then(response => response.json())
+      .then(data => {
+        if (data.success) {
+          console.log('Pi volume ingesteld op', volume + '%');
+          
+          if (previewAudio && previewAudio.src) {
+            previewAudio.play().catch(e => {
+              console.log('Audio test mislukt:', e);
+              alert('Volume ingesteld, maar audio test mislukt. Controleer HDMI verbinding.');
+            });
+          } else {
+            alert(`Pi HDMI volume ingesteld op ${volume}%`);
+          }
+        } else {
+          alert('Fout bij instellen volume: ' + data.error);
+        }
+      })
+      .catch(error => {
+        console.error('Netwerk fout:', error);
+        alert('Kon volume niet instellen. Controleer verbinding.');
+      });
+    }, 300);
+
+    // Optimize tab switching
+    function setupTabs() {
+      const tabBtns = document.querySelectorAll('.tab-btn');
+      const tabContents = document.querySelectorAll('.tab-content');
+      
+      // Gebruik event delegation voor tab clicks
+      document.querySelector('.tab-navigation').addEventListener('click', function(e) {
+        const btn = e.target.closest('.tab-btn');
+        if (!btn) return;
+        
+        const targetTab = btn.getAttribute('data-tab');
+        
+        // Remove active class from all buttons and contents
+        tabBtns.forEach(b => b.classList.remove('active'));
+        tabContents.forEach(c => c.classList.remove('active'));
+        
+        // Add active class to clicked button and corresponding content
+        btn.classList.add('active');
+        document.getElementById(targetTab + '-tab').classList.add('active');
+        
+        // Save active tab to localStorage
+        localStorage.setItem('activeSettingsTab', targetTab);
+      });
+      
+      // Restore last active tab
+      const savedTab = localStorage.getItem('activeSettingsTab');
+      if (savedTab) {
+        const savedBtn = document.querySelector(`[data-tab="${savedTab}"]`);
+        const savedContent = document.getElementById(savedTab + '-tab');
+        
+        if (savedBtn && savedContent) {
+          tabBtns.forEach(b => b.classList.remove('active'));
+          tabContents.forEach(c => c.classList.remove('active'));
+          
+          savedBtn.classList.add('active');
+          savedContent.classList.add('active');
+        }
+      }
+    }
+
+    // Initialize on load
+    window.addEventListener('load', function() {
+      if (audioSelect && previewAudio) {
+        previewAudio.src = `/static/clips/${audioSelect.value}`;
+      }
       
-      // Setup theme toggle
       setupThemeToggle();
       updateThemeIcon();
-      
-      // Setup tabs
       setupTabs();
-    };
+    });
 
     // Theme toggle functionaliteit (gekopieerd van index.html)
     function setupThemeToggle() {
@@ -387,85 +484,6 @@
         }
       }
     }
-
-    // Tab functionality
-    function setupTabs() {
-      const tabBtns = document.querySelectorAll('.tab-btn');
-      const tabContents = document.querySelectorAll('.tab-content');
-      
-      tabBtns.forEach(btn => {
-        btn.addEventListener('click', () => {
-          const targetTab = btn.getAttribute('data-tab');
-          
-          // Remove active class from all buttons and contents
-          tabBtns.forEach(b => b.classList.remove('active'));
-          tabContents.forEach(c => c.classList.remove('active'));
-          
-          // Add active class to clicked button and corresponding content
-          btn.classList.add('active');
-          document.getElementById(targetTab + '-tab').classList.add('active');
-          
-          // Save active tab to localStorage
-          localStorage.setItem('activeSettingsTab', targetTab);
-        });
-      });
-      
-      // Restore last active tab
-      const savedTab = localStorage.getItem('activeSettingsTab');
-      if (savedTab) {
-        const savedBtn = document.querySelector(`[data-tab="${savedTab}"]`);
-        const savedContent = document.getElementById(savedTab + '-tab');
-        
-        if (savedBtn && savedContent) {
-          // Remove active from all
-          tabBtns.forEach(b => b.classList.remove('active'));
-          tabContents.forEach(c => c.classList.remove('active'));
-          
-          // Activate saved tab
-          savedBtn.classList.add('active');
-          savedContent.classList.add('active');
-        }
-      }
-    }
-
-    // Pi HDMI Volume functies
-    function updateVolumeDisplay(value) {
-      document.getElementById('volumeDisplay').textContent = value + '%';
-    }
-
-    function testPiVolume() {
-      const volume = document.getElementById('piVolumeSlider').value;
-      
-      // Verstuur volume naar backend
-      fetch('/api/set-pi-volume', {
-        method: 'POST',
-        headers: { 'Content-Type': 'application/json' },
-        body: JSON.stringify({ volume: parseInt(volume) })
-      })
-      .then(response => response.json())
-      .then(data => {
-        if (data.success) {
-          console.log('Pi volume ingesteld op', volume + '%');
-          
-          // Test audio afspelen
-          const audio = document.getElementById('previewAudio');
-          if (audio && audio.src) {
-            audio.play().catch(e => {
-              console.log('Audio test mislukt:', e);
-              alert('Volume ingesteld, maar audio test mislukt. Controleer HDMI verbinding.');
-            });
-          } else {
-            alert(`Pi HDMI volume ingesteld op ${volume}%`);
-          }
-        } else {
-          alert('Fout bij instellen volume: ' + data.error);
-        }
-      })
-      .catch(error => {
-        console.error('Netwerk fout:', error);
-        alert('Kon volume niet instellen. Controleer verbinding.');
-      });
-    }
   </script>
 </body>
 </html>