As the title says, there are no gun sounds or music playing during campaign mode. In addition, the developer commentary audios don't play; when I 'use' dev commentary bubbles, the name of the dev comes up and initiates a scene but no audio plays.
I've read solutions such as "launch from the CoF folder" but the issue remains. People seem to think it's the Steam overlay; I tried disabling the Steam overlay but then when I try to start the game I get an error message and it won't start. I have also redownloaded the game.
Does anyone else have any ideas about how to fix this issue? I'm assuming it's a compatibility thing with laptops and I figure that I am not the only person with this issue. Thanks for any help that you can offer.

Regards, comrade pete