Run it
Copy the script and paste it into your executor.
local class_check = game.IsA
local sound = Instance.new('Sound')
local sound_stop = sound.Stop
local get_descendants = game.GetDescendants
for i,v in next, get_descendants(game) do
if class_check(v,"Sound") then
sound_stop(v)
end
end
-- release variables into the wild, aka let them be used again
get_descendants = nil
sound:Remove()
-- :triggered:
sound = nil
get_descendants = nil
sound_stop = nil
stop every sound in the game (on client or on everyone, depends if respectfilteringenabled is on)

Universal