Low FPS on main window - high fps on multiple others.

Hi guys,

I'm new to ISBoxer, so ELI5 if possible :).

I started boxing last week. 3 WoW accounts at the same time and all has been good. I'd leveled them all up to 100 and started running some farms.

I logged on thismorning to do a dual box for a character on my main account and was met with very low FPS. Just 19 / 20 on minimal settings. Then I noticed that my secondary window was still running maxed out at a solid 60. I swapped back to this window and it instantly dropped to 20FPS.

It almost seems as if the windows are detecting that they are the wrong way around. I've done a full uninstall / reinstall and still have the same issues (Now replicated on all of my sets).

Any ideas for a fix?