My program has high CPU

I want this program to run in the background all the time. What it does is when you click the middle mouse button it brings up the Win7 task switcher.

When my program runs it runs at about 24% cpu utilization

#include <misc.au3>
While 1
If _IsPressed(04) Then
	 Run(@ComSpec & " /c " & "C:\Windows\System32\rundll32.exe DwmApi #105")
		 Sleep(3000)
EndIf
WEnd

Does anyone have any ideas?

For a different approach, I was also trying to get the hotkeyset to work but could not get it to work with the middle mouse button. HotKeySet("_IsPressed(04)","function") does nothing.

Thx for your time