diff --git a/egs/librispeech/ASR/pruned_transducer_stateless7/train.py b/egs/librispeech/ASR/pruned_transducer_stateless7/train.py
index af7503ada..a1664df3f 100755
--- a/egs/librispeech/ASR/pruned_transducer_stateless7/train.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless7/train.py
@@ -155,7 +155,7 @@ def add_model_arguments(parser: argparse.ArgumentParser):
     parser.add_argument(
         "--pos-head-dim",
         type=str,
-        default="4",
+        default="2",
         help="Positional-encoding dimension per head in encoder stacks: a single int or comma-separated list."
     )