CfgSFX .ogg sound and MP (probab)

[Aeon 0]

I would know something about CfgSFX :

sfxfile, vol, frq, probab, min_delay, mid_delay, max_delay

Does probability (random parameter) is local : with different sounds played on different clients at the same moment. Or is the server that tell to all clients "Right now, play Sound_1 (this and not another)" ?

We know ogg is a great compression format, but we should not use widely. Some people have noticed important lag problem during MP game while SP running well, the ogg incriminated was a weapon sound (inside an addon). I guess each time that weapon was fired the server told to all clients to play the ogg sound.

Maybe a low-end computer (local or server) had difficulty to *uncompress* ogg and drag all others in some desynchronisation issue ? Would this mean every clients send to server a "ready to play" and/or "sound played" signal ?

I don't understand much about this, so I wonder if it would be advised to use ogg sound in CfgSFX (my sounds are huge, I have to not let them uncompressed just because a doubt)