Anyone have any suggestions on how to apply a low pass filter to all world sounds (like gunshots etc) when the player goes underwater?
have you tried a Reverb Volume?
Thanks for the reply @Chosker. What I mean is how to manipulate all other game sounds based on the event of the player submerging in water. I know how to achieve the sound fx I’m after.
that’s why I suggested it. Reverb Volumes manipulates all game sounds when the player enters it 
Hmmm, interesting. I wasn’t aware of this. I may b able to extend it to get the low pass filter I need. Cheers