No audio from echo show to doorbell

Just got a ring doorbell (Wired) and was trying to set it up before installing it on the front door, but i cannot seem to get either our echo show 8 (living room) or echo show5 (upstairs) and not even our alexa echo to send audio to the doorbell push. Even my Iphone 6 isn't able to talk to the Ring doorbell Wired. I get audio from the doorbell but not back to the doorbell from any device. Have I been sent a dud? I have read about others problems with the same thing, and although pictures are ok and detection is ok, its the reverse audio to the doorbell we are struggling with. And yes I have tried a hard re-set using the black button with orange dot on to do the reset (pressing it for 20 seconds etc) Iphone update ios 12.5.4 is inuse on the phone. The doorbell is hard wired to a Ring Power supply (plug in adaptor 2nd generation)