Copy the contents between the dashes and save as a .ahk file
----------------------
#NoTrayIcon
F1::Send {Volume_Mute}
F2::Send {Volume_Down}
F3::Send {Volume_Up}
F5::Send {Media_Play_Pause}
F6::Send {Media_Stop}
F7::Send {Media_Prev}
F8::Send {Media_Next}
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http://www.neowin.net/forum/topic/1110785-autohotkey-script-for-keyboards-lacking-media-keys/

Posted by Dennis W, originally by Tracker1, modified for pastebin by Keegan Jacobson (keeganjacobson)