diff --git a/web_server.py b/web_server.py
index 8c9c18aa..f18175fb 100644
--- a/web_server.py
+++ b/web_server.py
@@ -12547,6 +12547,12 @@ def stream_library_audio():
             return jsonify({"error": "path is required"}), 400
         resolved = _resolve_library_file_path(raw_path)
         if not resolved or not os.path.exists(resolved):
+            # Not on disk — same Navidrome stream fallback as /api/library/play
+            # (#809), so crossfade preload of the NEXT track works for streamed
+            # libraries too. Resolves the song id by path (DB lookup).
+            stream_url = _build_library_stream_url(request.args.get('track_id'), raw_path)
+            if stream_url:
+                return _proxy_stream_url_with_range(stream_url)
             return jsonify({"error": _get_file_not_found_error(raw_path)}), 404
         return _serve_audio_file_with_range(resolved)
     except Exception as e:
diff --git a/webui/static/media-player.js b/webui/static/media-player.js
index 4dff3642..4f155e92 100644
--- a/webui/static/media-player.js
+++ b/webui/static/media-player.js
@@ -1871,7 +1871,10 @@ function npStartCrossfade(nextIdx, next) {
 
     const targetVol = audioPlayer.volume; // fade the new track up to current level
     npXfadeMainVol = targetVol;            // remember to restore on abort
-    xa.src = `/stream/library-audio?path=${encodeURIComponent(next.file_path)}&t=${Date.now()}`;
+    // Pass the server song id so a streamed (un-mounted) Navidrome track can
+    // crossfade-preload via the server stream API too (#809).
+    const _xfTid = next.id ? `&track_id=${encodeURIComponent(next.id)}` : '';
+    xa.src = `/stream/library-audio?path=${encodeURIComponent(next.file_path)}${_xfTid}&t=${Date.now()}`;
     xa.volume = 0;
     xa.play().then(() => {
         const fadeMs = NP_CROSSFADE_SECONDS * 1000;