diff --git a/vggish.py b/vggish.py
index dfc3de2..3983341 100644
--- a/vggish.py
+++ b/vggish.py
@@ -66,6 +66,8 @@ class Vggish(NNOperator):
             except Exception as e:
                 log.error("Fail to load audio data.")
                 raise e
+        else:
+            log.error(f"Invalid input audio: {type(audio)}")
         return audio_tensors