diff --git a/ultralytics/data/loaders.py b/ultralytics/data/loaders.py
index 2cc67d2c..d6e6b376 100644
--- a/ultralytics/data/loaders.py
+++ b/ultralytics/data/loaders.py
@@ -545,7 +545,7 @@ def get_best_youtube_url(url, method="pytube"):
     """
     if method == "pytube":
         # Switched from pytube to pytubefix to resolve https://github.com/pytube/pytube/issues/1954
-        check_requirements("pytubefix")
+        check_requirements("pytubefix==6.3.4")  # bug in 6.4.2 https://github.com/JuanBindez/pytubefix/issues/123
         from pytubefix import YouTube
 
         streams = YouTube(url).streams.filter(file_extension="mp4", only_video=True)