In the update v 1.36 replaced the sound of the firing from all automatic grenade launcher.
I think the old sound was better.
And now, the old sound removed from game absolutely!
Please use the old sound also. May be at firing at least one of the side to the conflict in the game. (For example for AAF or CSAT only).
Or use the old sound only for stationary grenade launchers and a new sound, only for grenade launchers mounted on vehicles.
Most of the sound variations make the game only better!