Why do you want to adjust the volume? Why not just assign the action to the waterfall itself, if you are not doing so already, and then use ent_playloop ( ENTITY*, SOUND*, var volume); function, with a volume of something greater than 100, which will then be heard from a greater distance, and it will become louder the closer you get to it. Check the manual for more info.

Yes, I want positional audio...thanks...lifesaver, if this works....probably will.

it works, thank you....I was making a mountain out of a mole hill. I knew it could not be that hard.