diff --git a/examples/wav2vec/config/pretraining/wav2vec2_large_librivox.yaml b/examples/wav2vec/config/pretraining/wav2vec2_large_librivox.yaml
index bee41157a9..3192ce4cba 100644
--- a/examples/wav2vec/config/pretraining/wav2vec2_large_librivox.yaml
+++ b/examples/wav2vec/config/pretraining/wav2vec2_large_librivox.yaml
@@ -18,6 +18,7 @@ task:
   normalize: true
 
 dataset:
+  batch_size: 4
   num_workers: 6
   max_tokens: 1200000
   skip_invalid_size_inputs_valid_test: true