The other question that springs to my mind is, how long did you let it burn before you put the meat on?
I use a Weber kettle lid that has 4 x 3/4" holes (I think 3/4") that would be 1.76" square, my new flat lids have 8 x 1/2" = 1.57" square, they both smoke fine, with a 2" hole you're looking at double the exhaust 3.14" square, so I doubt you're getting stale smoke.
It could also be a rogue bag of charcoal that had at some time in it's life got wet, and dried funky, I've had this happen with one bag of Rancher, it was hard to light and wouldn't maintain temperature once it was lit.
"There is no such thing as a little garlic." A.Baer