diff --git a/core/deezer_download_client.py b/core/deezer_download_client.py
index 1d7dccc7..d3a13d26 100644
--- a/core/deezer_download_client.py
+++ b/core/deezer_download_client.py
@@ -613,8 +613,11 @@ class DeezerDownloadClient(DownloadSourcePlugin):
             logger.error("Deezer not authenticated — cannot download")
             return None
         if self._engine is None:
-            logger.error("Deezer client has no engine reference — cannot dispatch download")
-            return None
+            # Raise rather than return None so the orchestrator's
+            # download_with_fallback surfaces a real warning + tries
+            # the next source. Returning None silently dropped the
+            # download with no user feedback (per JohnBaumb).
+            raise RuntimeError("Deezer client has no engine reference — cannot dispatch download")
 
         # Parse filename: "track_id||display_name"
         parts = filename.split('||', 1)
diff --git a/core/download_engine/engine.py b/core/download_engine/engine.py
index a1391111..8aaa07e8 100644
--- a/core/download_engine/engine.py
+++ b/core/download_engine/engine.py
@@ -277,15 +277,21 @@ class DownloadEngine:
     #
     # All methods are async to match the per-plugin contract.
 
-    async def get_all_downloads(self):
+    async def get_all_downloads(self, exclude: Tuple[str, ...] = ()):
         """Aggregated view across every registered plugin's active
         downloads. Per-plugin exceptions are swallowed (one source
         failing shouldn't take down cross-source aggregation) but
         logged at debug level — same defensive shape the legacy
-        orchestrator had."""
+        orchestrator had.
+
+        ``exclude`` skips named sources entirely. The download monitor
+        passes ``('soulseek',)`` so it doesn't double-fetch slskd
+        transfers (it already pulled them via the slskd transfers
+        endpoint earlier in the same loop).
+        """
         all_downloads = []
         for source_name, plugin in self._plugins.items():
-            if plugin is None:
+            if plugin is None or source_name in exclude:
                 continue
             try:
                 all_downloads.extend(await plugin.get_all_downloads())
diff --git a/core/downloads/monitor.py b/core/downloads/monitor.py
index d08843a4..ff939352 100644
--- a/core/downloads/monitor.py
+++ b/core/downloads/monitor.py
@@ -273,7 +273,13 @@ class WebUIDownloadMonitor:
                 all_downloads = []
                 if download_orchestrator and hasattr(download_orchestrator, 'engine'):
                     try:
-                        all_downloads = run_async(download_orchestrator.engine.get_all_downloads())
+                        # Exclude soulseek — slskd transfers were already
+                        # pulled via the transfers/downloads endpoint above.
+                        # Without the exclude both fetch paths run, doubling
+                        # the per-tick slskd API hit.
+                        all_downloads = run_async(
+                            download_orchestrator.engine.get_all_downloads(exclude=('soulseek',))
+                        )
                     except Exception:
                         pass
                 for download in all_downloads:
diff --git a/core/hifi_client.py b/core/hifi_client.py
index cf383b52..8fa51cdd 100644
--- a/core/hifi_client.py
+++ b/core/hifi_client.py
@@ -579,8 +579,11 @@ class HiFiClient(DownloadSourcePlugin):
             logger.error(f"Invalid filename format: {filename}")
             return None
         if self._engine is None:
-            logger.error("HiFi client has no engine reference — cannot dispatch download")
-            return None
+            # Raise rather than return None so the orchestrator's
+            # download_with_fallback surfaces a real warning + tries
+            # the next source. Returning None silently dropped the
+            # download with no user feedback (per JohnBaumb).
+            raise RuntimeError("HiFi client has no engine reference — cannot dispatch download")
 
         track_id_str, display_name = filename.split('||', 1)
         try:
diff --git a/core/qobuz_client.py b/core/qobuz_client.py
index 48ceeb08..745bf27d 100644
--- a/core/qobuz_client.py
+++ b/core/qobuz_client.py
@@ -899,8 +899,11 @@ class QobuzClient(DownloadSourcePlugin):
             logger.error(f"Invalid filename format: {filename}")
             return None
         if self._engine is None:
-            logger.error("Qobuz client has no engine reference — cannot dispatch download")
-            return None
+            # Raise rather than return None so the orchestrator's
+            # download_with_fallback surfaces a real warning + tries
+            # the next source. Returning None silently dropped the
+            # download with no user feedback (per JohnBaumb).
+            raise RuntimeError("Qobuz client has no engine reference — cannot dispatch download")
 
         track_id_str, display_name = filename.split('||', 1)
         try:
diff --git a/core/soundcloud_client.py b/core/soundcloud_client.py
index b942a292..530d6f72 100644
--- a/core/soundcloud_client.py
+++ b/core/soundcloud_client.py
@@ -335,8 +335,11 @@ class SoundcloudClient(DownloadSourcePlugin):
             logger.error(f"Missing SoundCloud track id or url in: {filename}")
             return None
         if self._engine is None:
-            logger.error("SoundCloud client has no engine reference — cannot dispatch download")
-            return None
+            # Raise rather than return None so the orchestrator's
+            # download_with_fallback surfaces a real warning + tries
+            # the next source. Returning None silently dropped the
+            # download with no user feedback (per JohnBaumb).
+            raise RuntimeError("SoundCloud client has no engine reference — cannot dispatch download")
 
         logger.info(f"Starting SoundCloud download: {display_name}")
 
diff --git a/core/tidal_download_client.py b/core/tidal_download_client.py
index aab53290..45bdd4b9 100644
--- a/core/tidal_download_client.py
+++ b/core/tidal_download_client.py
@@ -619,8 +619,11 @@ class TidalDownloadClient(DownloadSourcePlugin):
             logger.error(f"Invalid filename format: {filename}")
             return None
         if self._engine is None:
-            logger.error("Tidal client has no engine reference — cannot dispatch download")
-            return None
+            # Raise rather than return None so the orchestrator's
+            # download_with_fallback surfaces a real warning + tries
+            # the next source. Returning None silently dropped the
+            # download with no user feedback (per JohnBaumb).
+            raise RuntimeError("Tidal client has no engine reference — cannot dispatch download")
 
         track_id_str, display_name = filename.split('||', 1)
         try:
diff --git a/core/youtube_client.py b/core/youtube_client.py
index 08993bab..b40f76cb 100644
--- a/core/youtube_client.py
+++ b/core/youtube_client.py
@@ -890,8 +890,11 @@ class YouTubeClient(DownloadSourcePlugin):
             logger.error(f"Invalid filename format: {filename}")
             return None
         if self._engine is None:
-            logger.error("YouTube client has no engine reference — cannot dispatch download")
-            return None
+            # Raise rather than return None so the orchestrator's
+            # download_with_fallback surfaces a real warning + tries
+            # the next source. Returning None silently dropped the
+            # download with no user feedback (per JohnBaumb).
+            raise RuntimeError("YouTube client has no engine reference — cannot dispatch download")
 
         video_id, title = filename.split('||', 1)
         youtube_url = f"https://www.youtube.com/watch?v={video_id}"
diff --git a/tests/downloads/test_deezer_pinning.py b/tests/downloads/test_deezer_pinning.py
index aa885907..f3f2cab2 100644
--- a/tests/downloads/test_deezer_pinning.py
+++ b/tests/downloads/test_deezer_pinning.py
@@ -48,12 +48,18 @@ def test_download_returns_none_when_not_authenticated(deezer_client_with_engine)
     assert result is None
 
 
-def test_download_returns_none_when_engine_not_wired():
+def test_download_raises_when_engine_not_wired():
+    """Defensive: client without engine reference must raise so the
+    orchestrator's download_with_fallback surfaces the error and
+    moves on to the next source. Returning None silently would drop
+    the download with no user feedback (per JohnBaumb)."""
+    import pytest
     client = DeezerDownloadClient.__new__(DeezerDownloadClient)
     client._engine = None
+    # Bypass auth gate so we exercise the engine check.
     client._authenticated = True
-    result = _run_async(client.download('deezer_dl', '12345||x', 0))
-    assert result is None
+    with pytest.raises(RuntimeError, match="engine reference"):
+        _run_async(client.download('deezer', 'v||t', 0))
 
 
 def test_download_track_id_stays_as_string(deezer_client_with_engine):
diff --git a/tests/downloads/test_download_engine.py b/tests/downloads/test_download_engine.py
index e4e9cff0..d46a0ee2 100644
--- a/tests/downloads/test_download_engine.py
+++ b/tests/downloads/test_download_engine.py
@@ -320,6 +320,24 @@ def test_engine_get_all_downloads_aggregates_across_plugins():
     assert {r.id for r in result} == {'yt-1', 'td-1', 'td-2'}
 
 
+def test_engine_get_all_downloads_skips_excluded_sources():
+    """Per JohnBaumb: monitor pulls slskd transfers via the
+    transfers/downloads endpoint earlier in its loop, so engine
+    aggregation must skip soulseek to avoid double-fetching."""
+    engine = DownloadEngine()
+    sl_plugin = _FakePlugin('soulseek', downloads=[_FakeStatus('sl-1', 'soulseek')])
+    yt_plugin = _FakePlugin('youtube', downloads=[_FakeStatus('yt-1', 'youtube')])
+    td_plugin = _FakePlugin('tidal', downloads=[_FakeStatus('td-1', 'tidal')])
+    engine.register_plugin('soulseek', sl_plugin)
+    engine.register_plugin('youtube', yt_plugin)
+    engine.register_plugin('tidal', td_plugin)
+
+    result = _run_async(engine.get_all_downloads(exclude=('soulseek',)))
+    ids = {r.id for r in result}
+    assert ids == {'yt-1', 'td-1'}
+    assert 'sl-1' not in ids
+
+
 def test_engine_get_all_downloads_swallows_per_plugin_exceptions():
     """One plugin throwing must NOT take down the whole list — same
     defensive behavior as the legacy orchestrator (matched by
diff --git a/tests/downloads/test_hifi_pinning.py b/tests/downloads/test_hifi_pinning.py
index 8111423f..24ca15f1 100644
--- a/tests/downloads/test_hifi_pinning.py
+++ b/tests/downloads/test_hifi_pinning.py
@@ -44,11 +44,16 @@ def test_download_returns_none_for_non_integer_track_id(hifi_client_with_engine)
     assert result is None
 
 
-def test_download_returns_none_when_engine_not_wired():
+def test_download_raises_when_engine_not_wired():
+    """Defensive: client without engine reference must raise so the
+    orchestrator's download_with_fallback surfaces the error and
+    moves on to the next source. Returning None silently would drop
+    the download with no user feedback (per JohnBaumb)."""
+    import pytest
     client = HiFiClient.__new__(HiFiClient)
     client._engine = None
-    result = _run_async(client.download('hifi', '12345||x', 0))
-    assert result is None
+    with pytest.raises(RuntimeError, match="engine reference"):
+        _run_async(client.download('hifi', 'v||t', 0))
 
 
 def test_download_returns_uuid_for_valid_filename(hifi_client_with_engine):
diff --git a/tests/downloads/test_qobuz_pinning.py b/tests/downloads/test_qobuz_pinning.py
index 9db40975..ab55d8ed 100644
--- a/tests/downloads/test_qobuz_pinning.py
+++ b/tests/downloads/test_qobuz_pinning.py
@@ -47,11 +47,16 @@ def test_download_returns_none_for_non_integer_track_id(qobuz_client_with_engine
     assert result is None
 
 
-def test_download_returns_none_when_engine_not_wired():
+def test_download_raises_when_engine_not_wired():
+    """Defensive: client without engine reference must raise so the
+    orchestrator's download_with_fallback surfaces the error and
+    moves on to the next source. Returning None silently would drop
+    the download with no user feedback (per JohnBaumb)."""
+    import pytest
     client = QobuzClient.__new__(QobuzClient)
     client._engine = None
-    result = _run_async(client.download('qobuz', '12345||x', 0))
-    assert result is None
+    with pytest.raises(RuntimeError, match="engine reference"):
+        _run_async(client.download('qobuz', 'v||t', 0))
 
 
 def test_download_returns_uuid_for_valid_filename(qobuz_client_with_engine):
diff --git a/tests/downloads/test_soundcloud_pinning.py b/tests/downloads/test_soundcloud_pinning.py
index 2a6e7127..4a5bc893 100644
--- a/tests/downloads/test_soundcloud_pinning.py
+++ b/tests/downloads/test_soundcloud_pinning.py
@@ -50,13 +50,16 @@ def test_download_returns_none_for_empty_track_id_or_url(sc_client_with_engine):
     assert _run_async(client.download('soundcloud', 'track123||', 0)) is None
 
 
-def test_download_returns_none_when_engine_not_wired():
+def test_download_raises_when_engine_not_wired():
+    """Defensive: client without engine reference must raise so the
+    orchestrator's download_with_fallback surfaces the error and
+    moves on to the next source. Returning None silently would drop
+    the download with no user feedback (per JohnBaumb)."""
+    import pytest
     client = SoundcloudClient.__new__(SoundcloudClient)
     client._engine = None
-    result = _run_async(client.download(
-        'soundcloud', 'sc-1||https://soundcloud.com/x/y||T', 0,
-    ))
-    assert result is None
+    with pytest.raises(RuntimeError, match="engine reference"):
+        _run_async(client.download('soundcloud', 'v||t', 0))
 
 
 def test_download_accepts_three_part_filename_with_display(sc_client_with_engine):
diff --git a/tests/downloads/test_tidal_pinning.py b/tests/downloads/test_tidal_pinning.py
index 405ee21b..74327f37 100644
--- a/tests/downloads/test_tidal_pinning.py
+++ b/tests/downloads/test_tidal_pinning.py
@@ -78,11 +78,16 @@ def test_download_returns_none_for_non_integer_track_id(tidal_client_with_engine
     assert result is None
 
 
-def test_download_returns_none_when_engine_not_wired():
+def test_download_raises_when_engine_not_wired():
+    """Defensive: client without engine reference must raise so the
+    orchestrator's download_with_fallback surfaces the error and
+    moves on to the next source. Returning None silently would drop
+    the download with no user feedback (per JohnBaumb)."""
+    import pytest
     client = TidalDownloadClient.__new__(TidalDownloadClient)
     client._engine = None
-    result = _run_async(client.download('tidal', '12345||x', 0))
-    assert result is None
+    with pytest.raises(RuntimeError, match="engine reference"):
+        _run_async(client.download('tidal', 'v||t', 0))
 
 
 def test_download_returns_uuid_for_valid_filename(tidal_client_with_engine):
diff --git a/tests/downloads/test_youtube_pinning.py b/tests/downloads/test_youtube_pinning.py
index 59cfb71b..4637af97 100644
--- a/tests/downloads/test_youtube_pinning.py
+++ b/tests/downloads/test_youtube_pinning.py
@@ -77,14 +77,16 @@ def test_download_returns_none_for_invalid_filename_format(yt_client_with_engine
     assert result is None
 
 
-def test_download_returns_none_when_engine_not_wired():
-    """Defensive: client without engine reference can't dispatch.
-    In production this never happens (orchestrator wires engine
-    immediately) but the soft-fail keeps tests + dev paths safe."""
+def test_download_raises_when_engine_not_wired():
+    """Defensive: client without engine reference must raise so the
+    orchestrator's download_with_fallback surfaces the error and
+    moves on to the next source. Returning None silently would drop
+    the download with no user feedback (per JohnBaumb)."""
+    import pytest
     client = YouTubeClient.__new__(YouTubeClient)
     client._engine = None
-    result = _run_async(client.download('youtube', 'v||t', 0))
-    assert result is None
+    with pytest.raises(RuntimeError, match="engine reference"):
+        _run_async(client.download('youtube', 'v||t', 0))
 
 
 def test_download_returns_uuid_download_id_for_valid_filename(yt_client_with_engine):
diff --git a/web_server.py b/web_server.py
index 74a332e7..77c100f5 100644
--- a/web_server.py
+++ b/web_server.py
@@ -2474,32 +2474,35 @@ def get_cached_transfer_data():
                     key = _make_context_key(transfer.get('username'), transfer.get('filename', ''))
                     live_transfers_lookup[key] = transfer
 
-            # Also add non-Soulseek downloads (avoid redundant slskd call through orchestrator).
-            # Every streaming source must appear here — task progress for in-flight
-            # downloads comes from this lookup. Missing a source = task.progress
-            # stays at 0 even when the underlying client knows the real percent.
+            # Also add non-Soulseek downloads. Soulseek is excluded
+            # because slskd's transfers endpoint was already pulled
+            # above — without the exclude both fetch paths run.
+            # Every streaming source must appear here — task progress
+            # for in-flight downloads comes from this lookup. Missing a
+            # source = task.progress stays at 0 even when the
+            # underlying client knows the real percent.
             try:
                 all_downloads = []
-                # Generic dispatch — engine returns active downloads
-                # across every plugin in one call, no per-source iteration.
                 if download_orchestrator and hasattr(download_orchestrator, 'engine'):
                     try:
-                        all_downloads = run_async(download_orchestrator.engine.get_all_downloads())
+                        all_downloads = run_async(
+                            download_orchestrator.engine.get_all_downloads(exclude=('soulseek',))
+                        )
                     except Exception:
                         pass
                 for download in all_downloads:
-                        key = _make_context_key(download.username, download.filename)
-                        # Convert DownloadStatus to transfer dict format
-                        live_transfers_lookup[key] = {
-                            'id': download.id,
-                            'filename': download.filename,
-                            'username': download.username,
-                            'state': download.state,
-                            'percentComplete': download.progress,
-                            'size': download.size,
-                            'bytesTransferred': download.transferred,
-                            'averageSpeed': download.speed,
-                        }
+                    key = _make_context_key(download.username, download.filename)
+                    # Convert DownloadStatus to transfer dict format
+                    live_transfers_lookup[key] = {
+                        'id': download.id,
+                        'filename': download.filename,
+                        'username': download.username,
+                        'state': download.state,
+                        'percentComplete': download.progress,
+                        'size': download.size,
+                        'bytesTransferred': download.transferred,
+                        'averageSpeed': download.speed,
+                    }
             except Exception as e:
                 logger.error(f"Could not fetch streaming source downloads: {e}")