diff --git a/src/Sound/Tidal/Pattern.hs b/src/Sound/Tidal/Pattern.hs
--- a/src/Sound/Tidal/Pattern.hs
+++ b/src/Sound/Tidal/Pattern.hs
@@ -1,7 +1,6 @@
 {-# LANGUAGE DeriveDataTypeable, TypeSynonymInstances, FlexibleInstances #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE DeriveFunctor #-}
-{-# LANGUAGE BangPatterns #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
 module Sound.Tidal.Pattern where
@@ -276,7 +275,7 @@
 
 -- | Like <*>, but the structure only comes from the left
 (<*) :: Pattern (a -> b) -> Pattern a -> Pattern b
-(<*) !pf@(Pattern Digital _) !px = Pattern Digital q
+(<*) pf@(Pattern Digital _) px = Pattern Digital q
   where q st = concatMap match $ query pf st
          where
             match (Event fWhole fPart f) =
@@ -285,7 +284,7 @@
               query px $ st {arc = xQuery fWhole}
             xQuery (Arc s _) = pure s -- for discrete events, match with the onset
 
-(<*) !pf !px = Pattern Analog q
+(<*) pf px = Pattern Analog q
   where q st = concatMap match $ query pf st
           where
             match (Event fWhole fPart f) =
@@ -295,7 +294,7 @@
 
 -- | Like <*>, but the structure only comes from the right
 (*>) :: Pattern (a -> b) -> Pattern a -> Pattern b
-(*>) !pf !px@(Pattern Digital _) = Pattern Digital q
+(*>) pf px@(Pattern Digital _) = Pattern Digital q
   where q st = concatMap match $ query px st
          where
             match (Event xWhole xPart x) =
@@ -304,7 +303,7 @@
               query pf $ fQuery xWhole
             fQuery (Arc s _) = st {arc = pure s} -- for discrete events, match with the onset
 
-(*>) !pf !px = Pattern Analog q
+(*>) pf px = Pattern Analog q
   where q st = concatMap match $ query px st
           where
             match (Event xWhole xPart x) =
diff --git a/src/Sound/Tidal/Stream.hs b/src/Sound/Tidal/Stream.hs
--- a/src/Sound/Tidal/Stream.hs
+++ b/src/Sound/Tidal/Stream.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE ConstraintKinds, GeneralizedNewtypeDeriving, FlexibleContexts, ScopedTypeVariables, BangPatterns #-}
+{-# LANGUAGE ConstraintKinds, GeneralizedNewtypeDeriving, FlexibleContexts, ScopedTypeVariables #-}
 {-# OPTIONS_GHC -fno-warn-missing-fields #-}
 
 module Sound.Tidal.Stream where
@@ -151,8 +151,9 @@
 
 -- Evaluation of pat is forced so exceptions are picked up here, before replacing the existing pattern.
 streamReplace :: Show a => Stream -> a -> ControlPattern -> IO ()
-streamReplace s k !pat
-  = E.catch (do pMap <- takeMVar $ sPMapMV s
+streamReplace s k pat
+  = E.catch (do let x = queryArc pat (Arc 0 0)
+                pMap <- seq x $ takeMVar $ sPMapMV s
                 let playState = updatePS $ Map.lookup (show k) pMap
                 putMVar (sPMapMV s) $ Map.insert (show k) playState pMap
                 calcOutput s
diff --git a/tidal.cabal b/tidal.cabal
--- a/tidal.cabal
+++ b/tidal.cabal
@@ -1,5 +1,5 @@
 name:                tidal
-version:             1.0.1
+version:             1.0.2
 synopsis:            Pattern language for improvised music
 -- description:
 homepage:            http://tidalcycles.org/