diff --git a/cocotbext/axi/axis.py b/cocotbext/axi/axis.py
index ef08c33..85f5c33 100644
--- a/cocotbext/axi/axis.py
+++ b/cocotbext/axi/axis.py
@@ -391,6 +391,7 @@ class AxiStreamSink(BusDriver):
             if compact:
                 frame.compact()
             return frame
+        return None
 
     def read(self, count=-1):
         while True: