@Peter, yup I didn't think it was Reaper but posted to alert and share ...
NI posted that W10 updates were the cause and they were talking to MS about it, and to delete a few updates for the time being. No mention of Win 7 by NI though a few people with win7 were having the same experience as me.
So, I uninstalled the last few updates and all is ok.
KB4486563
KB4483458
KB4480063
These are the latest up dates for 2019. Not sure if it was just one of them so did all three till proper solution is found.