diff --git a/requirements.txt b/requirements.txt
index 58cf9596..d4d24f0f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,7 @@ typing_extensions>=4.1.0
 dataclasses ; python_version<"3.7"
 
 # Third-party
-av
+av<14
 click
 glfw>=2.0.0
 msgpack>=1.0.0