No sound effects of guns, ghosts, foot steps, etc

When i open crossfire, i login and enter any game whether a ghost game or a team death match
when i start the game, i shoot some one, i got a headshot and i heard the sound

but the problem is i cant hear the gun muzzle sound or footsteps and i cant hear ghosts breath or knifes slashes with and without headphones

i can just hear radio messages, headshots and multi kills.

i opened my laptop and the sounds was there so i copied the rez files to my computer and replaced it but it didnt work

whats the problem?