WoW freezes sometimes
Firstly, I want to say that I am new to to ISBoxer so apologies if this is something very easy and simple fix that I haven't had the chance to discover yet! Secondly, ISBoxer is an awesome software and it works very good, but I have one very specific issue. From time to time, especially when loading maps/dungeons in WoW, one or two accounts will freeze. I multibox with 5 accounts, where one is my main account and 4 others are RAF's. I am always checking my task manager if the issue is too high usage of CPU but it truely never hits the "roof" (100%). This issue is not only happening when loading but also when questing and such, so I am pretty much limited to RDF only with myself, sadly. How I solve the "loading dungeon" issue is that I let one account load the map only and then let the others load one by one which isn't that big of an issue. But sadly I would also like to quest a bit with 5 players as RAF ends close to maximum level and we all know (who have been leveling in WoW) that it's pretty boring to grind same dungeons over and over again.
My specs can be found on this website here, where I even tested my computer to see if there was something wrong there: http://www.3dmark.com/3dm/17337723 Drivers are up to date. A little correction from that website, I am using 390 and not 290, somehow it confused itself (I checked in my system information just to be sure). Using 2 screens, first for my main and second for 4 boxes looking something like this:

Windows 10 is used as OS, as can be seen in the picture as well.
Any help will do!