My xmonad config - programmer's dvorak ok workspace switching, caps=ctrl, working matlab, laptop volume keys

xmonad.hs

import qualified Data.Map as M
import XMonad
import qualified XMonad as XMonad
import XMonad.Hooks.SetWMName
import qualified XMonad.StackSet as W

myWorkspaces = map show [1..9]
myNumRow = [xK_ampersand
           , xK_bracketleft
           , xK_braceleft
           , xK_braceright
           , xK_parenleft
           , xK_equal
           , xK_asterisk
           , xK_parenright
           , xK_plus] 

myKeys :: XConfig Layout -> M.Map (KeyMask, KeySym) (X ())
myKeys conf@(XConfig {modMask = modm}) =
  M.fromList $ [((m.|. modm, k), windows $ f i)
             | (i,k) <- zip (XMonad.workspaces conf) myNumRow
             , (f,m) <- [(W.greedyView, 0), (W.shift, shiftMask)]]
  ++ [((noModMask, 0x1008ff12), getMute >>= \m -> setMute (not m :: Bool) >> return ())
     ,((noModMask, 0x1008ff11), setMute False >> lowerVolume 4 >> return ())
     ,((noModMask, 0x1008ff13), setMute False >> raiseVolume 4 >> return ())
     ]


-- Matlab Java gui workaround.
myStartupHook = setWMName "LG3D" 

------------------------------------------------------------------------------
main = xmonad $ defaultConfig { terminal = "gnome-terminal"
                              , modMask = mod4Mask
                              , keys    = \c -> myKeys c `M.union`
                                          (keys defaultConfig c)
                              , startupHook = myStartupHook
                              }

noob here. xmona gets angry and throws a bunch of Not in scope error relating to get/set Mute and lower/Raise volume. What do I do?

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