diff --git a/midi.cabal b/midi.cabal
--- a/midi.cabal
+++ b/midi.cabal
@@ -1,5 +1,5 @@
 Name:             midi
-Version:          0.1.7
+Version:          0.1.7.1
 License:          GPL
 License-File:     LICENSE
 Author:           Henning Thielemann <haskell@henning-thielemann.de>
@@ -30,7 +30,7 @@
 Source-Repository this
   type:     darcs
   location: http://code.haskell.org/~thielema/midi/
-  tag:      0.1.7
+  tag:      0.1.7.1
 
 Flag splitBase
   description: Choose the new smaller, split-up base package.
diff --git a/src/Sound/MIDI/Message/Channel/Mode.hs b/src/Sound/MIDI/Message/Channel/Mode.hs
--- a/src/Sound/MIDI/Message/Channel/Mode.hs
+++ b/src/Sound/MIDI/Message/Channel/Mode.hs
@@ -56,7 +56,7 @@
 This function is also used in alsa-midi,
 we could give it the result type @Parser.PossiblyIncomplete T@ otherwise.
 -}
-fromControllerValue :: Integral a => (a, a) -> (Maybe UserMessage, T)
+fromControllerValue :: (Show a, Integral a) => (a, a) -> (Maybe UserMessage, T)
 fromControllerValue (mode,x) =
    case mode of
       0x78 ->
@@ -86,7 +86,7 @@
 
 
 checkValidValue ::
-   Integral a => String -> [a] -> a -> Maybe UserMessage
+   (Show a, Integral a) => String -> [a] -> a -> Maybe UserMessage
 checkValidValue name validValues value =
    toMaybe
       (not (elem value validValues))