diff --git a/backend/api/assets_serving.py b/backend/api/assets_serving.py
index b9ad6037..527b16e3 100644
--- a/backend/api/assets_serving.py
+++ b/backend/api/assets_serving.py
@@ -99,5 +99,10 @@ async def serve_voice_sample(
         raise HTTPException(status_code=404, detail="Asset not found")
 
     media_type = _get_media_type(safe_filename)
-    logger.info(f"[Assets] Serving voice sample: {safe_filename} ({media_type}, {file_path.stat().st_size} bytes)")
+    file_size = file_path.stat().st_size
+    first_bytes_hex = "N/A"
+    if file_size > 0:
+        with open(file_path, 'rb') as f:
+            first_bytes_hex = f.read(16).hex()
+    logger.warning(f"[Assets] Serving voice sample: {safe_filename} ({media_type}, {file_size} bytes, first_16hex: {first_bytes_hex})")
     return FileResponse(file_path, media_type=media_type)
\ No newline at end of file