If you use any sound mods (whether your own, or from workshop) you might have noticed problems. The problems you might have encountered may include no audio, out-of-sync sound, and static. To fix this you need to enable console. To open console press the key right below Esc (for American kb's that would be this key `/~).
Now you can either manually enter this command:
OR bind it to a key of your choice.
To bind it to the 'Home' key, enter the command below in console:
bind "home" "snd_restart"
It is common for your screen to pause & audio to become mute for a moment or two.
This should fix sound issues. If it does not resolve your issues, please verify Insurgency or simply remove offending sound mods.