you just need to click subscribe, then let steam download it before enter the game. And use snd_restart ingame console when it's not automatically loaded. Usually it is not necessary.

Cheers man, will check it out. Does it work out of box or do I need to tweak the game myself as well?

GG WP, btw I make sound mods, give it a try if you're interested:
http://v1.steam.hlxgame.cc/sharedfiles/filedetails/?id=889236432