Problem with ring doorbell pro

Hi
Hope you can help I’ve installed a new ring pro doorbell via a genuine din rail transformer voltage is 20v which is excellent the doorbell is only 7mts from router no obstacles yet it’s constantly buzzing on live view and the delay is bad the speed of my internet is excellent and I’ve tried all the resets etc suggested I purchased a ring chime pro today which I thought might help but after 3hours of attempting to connect it won’t connect to my WiFi although the chime that came with the doorbell is fine I’ve tried all the resets on both the app devices and chime pro any help much appreciated