'definesoundv <soundID> <file> <pitch_lower> <pitch_upper> <priority> <type> <distance> <volume>':
Variant of definesound, takes one extra argument which sets the global volume for all instances of this sound.
The second to last parameter specifies how far a sound is audible, like the original 'definesound' command.

'setactorsoundvolume <spriteID> <soundID> <newVolume>':
Like 'setactorsoundpitch', allows scripts to change the volume of currently active sounds,
which are addressed based on sprite and sound ID.

'setglobalsoundvolume <soundID> <newVolume>':
Alters the volume of all future instances of the corresponding sound ID.
However, it does not affect currently active sounds.

For all commands, <volume> ranges from 0 to 4096, where 1024 is the default volume set by 'definesound'.