I have noticed mine get super hot quickly as well. It does get annoying. Especially when you have a horse who isn't a fan of ears being clipped.
After a near castastrophe in clipping his ears, I bought some Wahl mini clippers for the face and ears, and he falls asleep when I do his ears now. The Andis just got too hot, to be comfortable for him.
Not sure what to do about it. I do a full body clip on my mini about three times a year, and it would go much faster if I didn't have to keep giving the blades a cooldown break.
"You're just as sane as I am."~Luna Lovegood.