I thought this mod idea would be good for helmet/mask/swat based skins here on the site.
A mod altering the original dialogue of Nick to sound almost radio-like.
As shown above, the mod does not work vpk wise and must be installed manually. Google yourself GCFScape if you do not have the program. It should be easy to find and easy to install. Extract the sound files into your l4d2 directory. Go into game and in your developer's console, type snd_updateaudiocache and that should properly sync the audio to work in game (type exit when you're done).
DO NOT USE AS A VPK FILE!