i don't if that is the cause because i'm still fiddling with isboxer myselft, but i had taht when i had toons in more than just one character set, and basically the macro was trying to follow toons that were not online at the time. (wrong FTL basically)
I'd suggest looking into the FTL modifyers (click your team name and check each slot) to make sure they are all valid.
Or you can try what I did when i had enough, and remove from isboxer all the toons taht are not in the current played team. (make a backup of the isboxer settings first)