Add configurable concurrent downloads setting

- New "Concurrent Downloads" dropdown on Settings page (1-10, default 3)
- Saved to download_source.max_concurrent config key
- All 6 batch creation sites use configured value instead of hardcoded 3
- Soulseek-only album downloads still use 1 worker (source reuse per user)
- Hybrid/YouTube/Tidal/Qobuz/Deezer albums use full configured concurrency

web_server.py

@@ -1896,6 +1896,23 @@ download_batches = {}  # batch_id -> {queue, active_count, max_concurrent}
 tasks_lock = threading.Lock()
 batch_locks = {}  # batch_id -> Lock() for atomic batch operations
 
+def _get_max_concurrent():
+    """Get configured max concurrent downloads. Default 3."""
+    return config_manager.get('download_source.max_concurrent', 3)
+
+def _get_batch_max_concurrent(is_album=False, source=None):
+    """Get max concurrent workers for a batch.
+    Soulseek album downloads always use 1 (source reuse per user).
+    Everything else uses the configured setting."""
+    if is_album and source in ('soulseek', None):
+        # Check if active source is soulseek
+        if source == 'soulseek':
+            return 1
+        mode = config_manager.get('download_source.mode', 'soulseek')
+        if mode == 'soulseek':
+            return 1
+    return _get_max_concurrent()
+
 # --- Session Download Statistics ---
 # Track individual download completions (matches dashboard.py behavior)
 session_completed_downloads = 0
@@ -21794,7 +21811,7 @@ def _process_wishlist_automatically(automation_id=None):
                     'playlist_name': playlist_name,
                     'queue': [],
                     'active_count': 0,
-                    'max_concurrent': 1 if current_cycle == 'albums' else 3,  # 1 worker for album source reuse, 3 for singles
+                    'max_concurrent': _get_batch_max_concurrent(is_album=(current_cycle == 'albums')),
                     'queue_index': 0,
                     'analysis_total': len(wishlist_tracks),
                     'analysis_processed': 0,
@@ -22692,7 +22709,7 @@ def start_wishlist_missing_downloads():
                 'playlist_name': playlist_name,
                 'queue': task_queue,
                 'active_count': 0,
-                'max_concurrent': 1 if category == 'albums' else 3,  # 1 worker for album source reuse, 3 for singles
+                'max_concurrent': _get_batch_max_concurrent(is_album=(category == 'albums')),
                 'queue_index': 0,
                 'analysis_total': len(wishlist_tracks),
                 'analysis_processed': 0,
@@ -27134,7 +27151,7 @@ def start_playlist_missing_downloads(playlist_id):
             download_batches[batch_id] = {
                 'queue': [],
                 'active_count': 0,
-                'max_concurrent': 3,
+                'max_concurrent': _get_max_concurrent(),
                 'queue_index': 0,
                 # Track state management (replicating sync.py)
                 'permanently_failed_tracks': [],
@@ -29131,7 +29148,7 @@ def start_missing_tracks_process(playlist_id):
             'playlist_name': playlist_name,
             'queue': [],
             'active_count': 0,
-            'max_concurrent': 1 if is_album_download else 3,  # Album/EP: 1 worker for source reuse; Playlist: 3 workers
+            'max_concurrent': _get_batch_max_concurrent(is_album=is_album_download),
             # Track state management (replicating sync.py)
             'permanently_failed_tracks': [],
             'cancelled_tracks': set(),
@@ -29229,7 +29246,7 @@ def start_missing_downloads():
             download_batches[batch_id] = {
                 'queue': [],
                 'active_count': 0,
-                'max_concurrent': 3,
+                'max_concurrent': _get_max_concurrent(),
                 'queue_index': 0,
                 # Track state management (replicating sync.py)
                 'permanently_failed_tracks': [],

webui/index.html

@@ -4245,6 +4245,24 @@
                                     </div>
                                 </div>
 
+                                <div class="form-group">
+                                    <label>Concurrent Downloads:</label>
+                                    <select id="max-concurrent-downloads" class="form-select">
+                                        <option value="1">1</option>
+                                        <option value="2">2</option>
+                                        <option value="3" selected>3 (Default)</option>
+                                        <option value="4">4</option>
+                                        <option value="5">5</option>
+                                        <option value="6">6</option>
+                                        <option value="8">8</option>
+                                        <option value="10">10</option>
+                                    </select>
+                                    <div class="setting-help-text">
+                                        Maximum simultaneous downloads per batch. Soulseek album downloads always use 1 worker
+                                        due to per-user upload limits. Higher values speed up large playlists and wishlists.
+                                    </div>
+                                </div>
+
                                 <!-- Hybrid Mode Settings (shown only when hybrid is selected) -->
                                 <div id="hybrid-settings-container" style="display: none;">
                                     <div class="setting-help-text">

webui/static/script.js

@@ -5781,6 +5781,7 @@ async function loadSettingsData() {
         // Populate Download Source settings
         document.getElementById('download-source-mode').value = settings.download_source?.mode || 'soulseek';
         document.getElementById('stream-source').value = settings.download_source?.stream_source || 'youtube';
+        document.getElementById('max-concurrent-downloads').value = settings.download_source?.max_concurrent || '3';
         loadHybridSourceOrder(settings);
         document.getElementById('tidal-download-quality').value = settings.tidal_download?.quality || 'lossless';
         document.getElementById('tidal-allow-fallback').checked = settings.tidal_download?.allow_fallback !== false;
@@ -6814,6 +6815,7 @@ async function saveSettings(quiet = false) {
             hybrid_secondary: document.getElementById('hybrid-secondary-source').value,
             hybrid_order: getHybridOrder(),
             stream_source: document.getElementById('stream-source').value,
+            max_concurrent: parseInt(document.getElementById('max-concurrent-downloads').value) || 3,
         },
         tidal_download: {
             quality: document.getElementById('tidal-download-quality').value || 'lossless',