CS:Source v92 hostage lips animation
 

Hello!
Hostages in CS Source server move their lips only when using default sounds.
If you change the sound (in the game_sounds_hostages script), then the lips do not move.
I assumed that this was due to the binding of the animation of the model to the sound, but during decompilation I did not find such an animation.

Who knows how to make a hostage's lips move with custom sound?