Strange hotkey conflict issue

While using Dorico on my laptop its down and up arrow keys are broken, so I was forced to use numpad arrows to work in Dorico. However, when for some strange reason when I use ALT + up (numpad) to move notes up in pitch in galley mode, the editor also zooms out. This is very distracting as you can maybe imagine.

I couldn’t find a conflicting hotkey option in the hotkey menu to disable this zoom out function… any ideas how to find where/what the conflicting option is?

Are you on Windows or macOS? I guess probably Windows? I wonder whether there is some other utility, or possibly some software associated with your graphics adaptor, that is intercepting these key commands?