I'd bet it's not factory damped, but rather done my an Altec installer/contractor. Look at the back of the flange. It looks like it was mounted on a baffle, as the egde isn't clean. Also, I think the shipping damage looks like a bad modification. I've never seen corners broken like that before. Usually it's at some diagonal, not a square chunk, like what would be the perfect shape to go around cabinet bracing.
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