WiFi Issues

Anybody else having the same problems and know a fix for this? Basically my router works perfect for every other device in my house, apart from when I’ve set the Ring Doorbell up (2nd Gen) I keep getting a live picture, then 20 seconds in I get ‘Weak connection is causing video issues’ then a black screen saying try again. I’ve done all the usual resets, a factory reset and started process all again, changed channel on router to 1-11 etc. my router is bang opposite my Ring Doorbell and I’ve got BT Fibre so shouldn’t be a problem when everything else works fine in the house, signal strength says good and RSSI fluctuates between 48 to 55! Have I got a faulty Video Doorbell or has anyone had similar issues and managed to fix it? Please let me know, Thanks.