diff --git a/espnet/nets/pytorch_backend/transformer/subsampling.py b/espnet/nets/pytorch_backend/transformer/subsampling.py
index a69bc09445f..f91d2906416 100644
--- a/espnet/nets/pytorch_backend/transformer/subsampling.py
+++ b/espnet/nets/pytorch_backend/transformer/subsampling.py
@@ -30,8 +30,8 @@ def __init__(self, message, actual_size, limit):
 
 def check_short_utt(ins, size):
     """Check if the utterance is too short for subsampling."""
-    if isinstance(ins, Conv2dSubsampling2) and size < 3:
-        return True, 3
+    if isinstance(ins, Conv2dSubsampling2) and size < 7:
+        return True, 7
     if isinstance(ins, Conv2dSubsampling) and size < 7:
         return True, 7
     if isinstance(ins, Conv2dSubsampling6) and size < 11: