Camera speaker issue

Hi. I installed the Yi Dome Guard at my home. It connected fine and the Kami app works… when I try the mic to speak there is no sound from the speakers. I put all the permissions, tried the intercom and the other way… my firmware is all up to date… I even installed the app on my old LG G6 phone and the same thing happened… they don’t hear me from the camera speakers… is it a hardware or a software issue.??