I noticed this in 9 as well, can’t recall if there was an issue in 7 (I skipped 8).
When performing normal operations like selecting objects and doing ctrl-c, ctrl-v to copy and paste, v (my shortcut to cycle the cursor), etc. Cubase will often behave as if I didn’t press the key, only recognizing it after multiple attempts in many cases.
I actually replaced my keyboard with a new one because I thought that was the problem. Turns out it does it with the new one as well. However, in the midst of all those ignored keystrokes, I can bring up the Windows Notepad app, Microsoft Word, etc. and there’s not a single dropped character, or so much as a hesitation. At this point I’m pretty confident that the behavior is local to Cubase.
Has anyone else experienced this, and is there any option or setting I might be missing to remedy it? When you can’t reliably use your keyboard in an application, it’s obviously a real workflow hinderence.