I would also change this be instead of
LoopVolume < 40
I would use System LoopVolume < 39 -> Set 'Loop' volume to -LoopVolume db
This will save some processing. As you lerp from 39 onwards, the values get progressively smaller, extra cpu cycles that aren't needed. IE it goes 0-39 fast but then 39-40 after a few seconds.