I have Manjaro Linux in VirtualBox, and in some applications such as the terminal the mouse wheel seems not to register many of the scroll ticks. Sometimes it scrolls fine, then suddenly it scrolls only half as much or stops scrolling at all. In other applications such as Firefox, the scroll wheel always works.
After some experimentation I found that I can't scroll at all while I'm moving the mouse pointer. Yet, when I hold the pointer perfectly still, scrolling works as expected.
There are some related questions on this site, but none have this specific issue caused by moving the mouse pointer while scrolling in Linux.