I get this problem both when playback is stopped, or the project is playing.
When clicking on Rewind or Fast forward, the position marker/cursor continues moving until Stop or Play is clicked, not when released as in previous versions of Cubase
The FF and RW work as they should, when I use the numeric keypad on the standard PC keyboard, it seems to be only clicking with the mouse that cases the error.
Just FYI
Cubase Artist 12
Windows 10 Pro 21H2