Magic Keyboard not working properly after Ventura upgrade

Since upgrading from Monterey 2 days ago my Magic Keyboard / Numeric Pad has gone totally crazy. Trying to write emails with Mail (or eM Client) the words join together, space bar doesn't work unless i do Option+Spacebar. The thing is it doesn't happen all the time, but fairly frequently. Same thing with typing in search bar on Safari. All other apps seem to work fine (although typing in boxes within some websites produce same problem). I rebooted in safe mode a few times and seemed to solve the problem only for it to reappear. I'm using iMac 27" new in 2019 with 48 GB RAM. Everything worked perfectly until upgrade to Ventura. Not sure if I've given enough info about the problem, but thanks in advance for any ideas / suggestions. I haven't heard of anyone else complaining of same prob.