Here is a simple Macro that will lower/increase the Windows System Volume. 
First, you need to download and install this little tool: http://www.softarium.com/soundvolumehotkeys/ 
It will run in the background and add the hotkeys ctrl up and ctrl down to modify the system volume. 
We can now use a WSR Macro to do this for us. 
You can say: volume up / louder or volume down / quiter
and also "silence i kill you" for mute and my personal favorite "turn it to eleven" for max volume ;) 
Best Regards
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 <?xml version="1.0" encoding="UTF-16"?>
 <speechMacros>
 <command>
 <listenFor>louder</listenFor>
 <listenFor>volume up</listenFor>
 <sendKeys>{{CTRL}}{{up}}{{up}}{{up}}{up}</sendKeys>
 </command>
 
 <command>
 <listenFor>quiter</listenFor>
 <listenFor>volume down</listenFor>
 <sendKeys>{{CTRL}}{{down}}{{down}}{{down}}{down}</sendKeys>
 </command>
 
 <command>
 <listenFor>mute</listenFor>
 <listenFor>silence i kill you</listenFor>
 <sendKeys>{{CTRL}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{{down}}{down}</sendKeys>
 </command>
 
 <command>
 <listenFor>max volume</listenFor>
 <listenFor>turn it to eleven</listenFor>
 <sendKeys>{{CTRL}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{{up}}{up}</sendKeys>
 </command>
 
 <Signature>
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 KUnVOBk3/CFLG4TQyRZD1BQ=
 </Signature>
 </speechMacros>
 
 
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Edited by molkemon - 13/May/2011 at 10:53pm