I make great cakes! Really. I use a mix but doctor it a bit and it's always nice and moist, flavorful, nice crumb...you get the picture. But when I take the same batter and pour it into cupcake papers to bake....they are kind of dry and "holey". What am I doing wrong, or do you need to adjust the recipe for cupcakes?
Sounds like they're overbaked. I bake cupcakes much hotter than a cake in a big pan (also because I'm at altitude and cakes tend to sink otherwise).
You can also drop the pan flat on the counter before they go in the oven to bring any bubbles out.
Check them much earlier than you may have been, and listen carefully for that noise which is your little cuppies saying "We're done!!"
Ah shucks. That's a bummer! Wonder if your doctored mix has too much liquid? I am scratch, but a few of my scratch recipes are heavier and don't make great cupcakes (too sticky to the paper). I'd watch your temp, bake at 350deg for about 14-18 min., take them out of the pan but leave in the paper liners. See if this doesn't help, hmm? Good luck! 
I bake my cupcakes at a bit higher heat than regular cakes and take them out in about 13 minutes or so. This has helped a lot. You have to get to the point when you take them out at the exact right moment that they're not underbaked or overbaked. It's just practice - but I use scratch recipes. Box may be a little different, not sure. You just want them to look like they're set. Not browned or anything.
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