No in game sound please help!

Hello I have decided to play garrysmod again but i came across a disturbing problem, there is no sound. When I start garrysmod I get the sound effect of hovering over the menu options but as soon as i start a game online or offline all sounds stop. I cant hear anything not even the menu options sounds work anymore after starting a game. I have reinstalled garrysmod 3 times and i know it is not my volume option in gmod or my pc thats the problem because of I hear the sound effect of hovering over menu options on start up. Any ideas? No sound is really ruining the game for me.