Login hangs on wakeup login Mint 19.2

Running a clean install of Mint 19.2 on Dell Optiplex 7010. If I leave my computer long enough to require logging back in, a large part of the time the keyboard will just freeze after entering only one or two characters of password. If I manage to enter entire password, it may take 30-60secs.to process,then fail. After hanging or password failing the first time, on second attempt everything works normally.Keyboard responds quickly and password is recognized in just a few secs. There are no keyboard issues in ordinary use, just the login. This occurs maybe 30% of the time. I have no idea how to troubleshoot the issue. I never had the problem in Mint 19.0.