This may be a bit of an unusual request, but I was wondering if it would be possible to add a feature to the sound system, where an event happens in the distance and the sound gets played later due to the sound having to travel through air at the speed of sound? For example, a lightning bolt strikes the ground off in the distance and there are multiple players which observe the lightning bolt. Each player is a different distance from the impact point, so the time at which they hear the thunder is a function of their distance from the impact point (~5 second delay per mile). One player might hear it instantly while another might hear it 5 seconds later.
I think if you wanted to get super technical, you could design the system such that the speed of sound is dependent on the density of the medium it is travelling through.
So, no sound in empty space due to no medium;
340.29 m / s at sea level through air medium
1482 m/s through water medium
5790 m/s through steel medium
(ref: Sound Speeds through Solids)
I imagine attenuation settings would also be affected by the medium through which sound travels through