Unable to detect microphone volume

Hi you all, I followed a guide (that can be found at http://sree.cc/corona-sdk/detect-microphone-volume-blowing-into-microphone) to try to detect the microphone volume.

The code I’ve used is:

[lua]

local _w = display.contentWidth

local _h = display.contentHeight

local background_ = display.newRect(0,0,_w,_h)
background_:setFillColor(255)

local text_ = display.newText(“Initial…”,200,10,nil,30)
text_:setTextColor(0)

local r = media.newRecording()
r:startRecording()
r:startTuner()

 
function soundDetector( event )
local v = r:getTunerVolume()
if v == 0 then
return
end

v = 20 * 0.301 * math.log(v)
m = v*10

if(m>= -50)then
text_.text = “High…”
background_:setFillColor(255,0,0)
elseif(m< -50 and m>-100)then
text_.text = “Medium…”
background_:setFillColor(0,0,255)
else
text_.text = “Low…”
background_:setFillColor(0,255,0)
end

end
Runtime:addEventListener( “enterFrame”, soundDetector )

[/lua]

the problem is that the console returns “Unexpected symbol near ‘,’” at line 7.

I tried to modify the code in:

[lua]

local _w = display.contentWidth

local _h = display.contentHeight

local background_ = display.newRect(0,0,_w,_h)

background_:setFillColor(255)

local r = media.newRecording()

r:startRecording()

r:startTuner()

function soundDetector( event )

local v = r:getTunerVolume()

if v == 0 then

return

end

v = 20 * 0.301 * math.log(v)

m = v*10

if(m>= -50)then

background_:setFillColor(255,0,0)

elseif(m< -50 and m>-100)then

background_:setFillColor(0,0,255)

else

background_:setFillColor(0,255,0)

end

end

Runtime:addEventListener( “enterFrame”, soundDetector )

[/lua]

but then the console returns the same error (Unexpected symbol near ‘,’) at the last line (“Runtime:addEventListener( “enterFrame”, soundDetector )”)

What can I do to fix this issue? thanks!