diff --git a/ttstoy/webui/app.py b/ttstoy/webui/app.py
index 0c0a6c5..098aefe 100644
--- a/ttstoy/webui/app.py
+++ b/ttstoy/webui/app.py
@@ -619,12 +619,15 @@ def api_mc_login():
 
 @app.route("/api/mc/voices", methods=["GET"])
 def api_mc_voices():
-    """List all predefined voices from the Chatterbox server."""
+    """List predefined voices from the Chatterbox server (excludes user-uploaded voices)."""
     try:
         chatterbox_url = get_chatterbox_url()
         r = requests.get(f"{chatterbox_url}/get_predefined_voices", timeout=10)
         r.raise_for_status()
-        return jsonify(r.json())
+        voices = r.json()
+        # Filter out user-uploaded voices (format: userid_name.wav where userid is numeric)
+        filtered = [v for v in voices if not v.get("filename", "").split("_")[0].isdigit()]
+        return jsonify(filtered)
     except Exception as e:
         return jsonify({"error": str(e)}), 502