...when they unplug the mouse, and plug it back in it fixes the issue.
Saying it out loud (in my head lol) has made me realise that as they are Interactive projectors, they are connected via USB for the interactive function.
Wondering if i need to update drivers. I updated the graphics drivers but it maybe a hardware/peripheral driver issue.
anything else to try as well, might as well post it as ive typed it lol!