Earpiece is quieter after replacing power flex

After Installing proximity sensor the earpiece is more quieter then before ( the volume is on max ). I tried to reassemble few times, but always same problem, does any have similar situation? By the way, everything is clear between earpiece and display.

And still something, the proxy sensor doesn't work, and it is for me one of often problems when I order it on ebay, on most of them proxy sensor doesn't work. Guys, do you have any seller for recommend to buy proximity sensor ( power flex ).