Not one I've noticed actually... I'd /bug that one when it is happening.
In fact, apart from the odd bit of NPC AI left in my henchmen (close to melee, flee from burn/caltrop patches) I'm very happy with them these days.
There is days where I think my pets hate me. Especially when I say "you stay here, passive mode" and look at them ignore my orders and attack the Backalley Brawler. 
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There is days where I think my pets hate me. Especially when I say "you stay here, passive mode" and look at them ignore my orders and attack the Backalley Brawler.
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They got bored. 
Personally I never noticed this. But than again, my MM is young and so far I've been only playing solo with him.
Anyone noticed when teamed with fellow Masterminds occasional the pets seem to be following the attack orders of another MM I have had this a few times now where the pets are set to passive but then rush off and attack the other MM target?