Ring doorbell cannot hear person at the door.

Hi I've set up my ring doorbell 2 today the device is only 2m away from the WiFi router . The sound from the person who has pressed the bell is so quietbi carnt hear them on my mobile phone. Also there is a pixel line all the way through the image any ideas as it has been set up justbas asked in the description. Any help would be appreciated. Just to confirm the people can her me but I carnt hear them.