Why does my disc still keep spinning when music is turned off?

So, the music plays and the Disc moves at the same time, but when it is turned of the disc still keeps moving.

local isOn = false
local Disc = script.Parent.Parent.Disc

function on()
    isOn = true
    script.Parent.Loop:Play()
    while true do
    wait(0.1)
    script.Parent.Parent.Disc.CFrame =
script.Parent.Parent.Disc.CFrame*CFrame.fromEulerAnglesXYZ(0,0.1,0)
    end 
end

function off()
    isOn = false
    script.Parent.Loop:Stop()
    wait(0.1)
    script.Parent.Parent.Disc.CFrame = script.Parent.Parent.Disc.CFrame*CFrame.fromEulerAnglesXYZ(0,0,0)
end

function onSelected(player,Choice)

    if Choice.Name == "on" then
        on()
    elseif Choice.Name == "off" then
        off()
    end
end

script.Parent.Dialog.DialogChoiceSelected:connect(onSelected)