Full disclosure, I live in Palm Springs but even so the balls feel like bricks and the felt is so thin and tight that the balls never fluff up.
I've tried Penn, Penn Pro, Penn ATP Tour, Wilson US Open, all hard as a rock.
There seems to be a bad batch of Penns going around now. I used two cans last week and they felt like they had way too much pressure and was hard and super bouncy. The other day I played with Dunlop ATP and it was much better.
Try hitting with a different (borrowed) racket and see if it makes a difference.
If so, try stringing your racket at a lower tension.
Until then, open can of balls the day before you intend to use them and see if that helps.