diff --git a/README.md b/README.md
index 0049fa4..75d0beb 100644
--- a/README.md
+++ b/README.md
@@ -106,6 +106,8 @@ play("alarm.wav")
 
 ### Async mode
 
+⚠️ The `async_mode` parameter has a default value of `False`
+
 ```python
 import time
 from nava import play, stop