diff --git a/tractor/_streaming.py b/tractor/_streaming.py
index 4ddb95c..e0879a3 100644
--- a/tractor/_streaming.py
+++ b/tractor/_streaming.py
@@ -274,9 +274,9 @@ class ReceiveMsgStream(trio.abc.ReceiveChannel):
     @asynccontextmanager
     async def subscribe(
         self,
-
     ) -> AsyncIterator[BroadcastReceiver]:
-        '''Allocate and return a ``BroadcastReceiver`` which delegates
+        '''
+        Allocate and return a ``BroadcastReceiver`` which delegates
         to this message stream.
 
         This allows multiple local tasks to receive each their own copy
@@ -692,6 +692,7 @@ class Context:
                             result = consume(msg)
                             if result:
                                 self._result = result
+                                break
 
                 if not self._result:
                     while True: