Entering text sends me to home screen

[anon(3900582)]

For what I've read here and in other forums quite a number of people has this problem:
Whenever I start typing in any app that requires input such as sms, a browser, maps, facebook, whatsapp, etc. I get returned to the home screen after entering 2 or 3 characters. Then I'm able to return to the app and keep typing with no further problem.
I have a rooted Galaxy Note 3 running Android 6.0.1 but I seems to happen in other versions of Android as well as iOS.
It happens with any keyboard, Samsung, Gboard, Swiftkey ...
This phone has a physical home button so the argument that I accidentally touch the home button while typing is not valid in this particular phone although it could be the case with phones that have a virtual home button.

I've tried many suggestions like rebooting or clearing the cache partition to no avail.

I've also tried to run CatLog to see what happens just before I'm sent to to home screen but the app doesn't read the system log, it just sits there with the loading circle spinning forever. Maybe CatLog it's not compatible with MarshMallow.

Has anybody had this problem and fixed it ?
I'm trying to avoid a hard reset at all costs ...