I just bought some 3/4 inch CDX plywood to act as an underflooring for my home gym. Usually I will lay down two sheets of plywood with a 1/2 inch thick rubber mat on top. Problem is, the plywood warped. No a huge warp, but enough so that when I stand on the center you can hear and feel it compress. Not a problem when I deadlift, but if I clean or dumbbell snatch I can fell and hear it.
Is there anyway to flatten these bastards out without having to be replaced.