See the wiki for more details
https://wow.gamepedia.com/API_MuteSoundFile
There already is an addon that can mute specific sounds
https://github.com/funkydude/MuteSoundFile
https://www.curseforge.com/wow/addons/mutesoundfile
Mute Annoying WoW Sounds will probably also be updated
https://www.curseforge.com/wow/addons/mute-wow-sounds
Example for muting the fizzle sounds:
local sounds = {
569772, -- sound/spells/fizzle/fizzleholya.ogg
569773, -- sound/spells/fizzle/fizzlefirea.ogg
569774, -- sound/spells/fizzle/fizzlenaturea.ogg
569775, -- sound/spells/fizzle/fizzlefrosta.ogg
569776, -- sound/spells/fizzle/fizzleshadowa.ogg
}
for _, fdid in pairs(sounds) do
MuteSoundFile(fdid)
end
You can put this in a WeakAura or in the REHack addon or make one yourself with https://addon.bool.no/