As there were a few topic that seem to be related we decided to make one topic so we can try to understand what is causing this. Let's start with what we know.
We have 21 people on file that reported this (that far below one promille of users)
3 have not replied to our attempts to get more info
9 have reported their issue solved
2 by using correct procedure
1 by making sure FPS was high enough
6 by re-installin