So we have hardwood floors in our house, that were put in a year ago and noticed a few of the boards really starting to bow up. From doing a bit of reading online I went and got a hygrometer (measures humidity) in the house. It's been as high as like 65% since I got it last week. It's supposed to be in the 35-55% from what I read. Obviously the weather has been crazy recently though. I know some expanding of the boards is normal in the summer but this seems beyond that.
We have a guy coming soon to check the AC to make sure that is working properly as I read that is a good play to start with regards to diagnosing the problem. Ideally, it's a small fix to the AC to put out less humidity but I don't know how realistic that is. I can't say that I have a good grasp on any of this stuff and am just trying to take care of the problem before it ruins our floors.
The A/C should help with some dehumidifying. If it's not enough, make sure you keep your ceiling fans on, and look into purchasing a smaller dehumidifier for the house, and use it in the room that has the hardwood. Or put it in an area central to the rooms that have hardwood. Check the A/C filter to make sure it's not all clogged to hell, also. Make sure windows are sealed well, and caulk around them if not. They'll let humidity and moisture in.
The A/C doesn't "put out" humidity, really. All an A/C unit does is suck in air in the house, pass it over refrigerated cold coils, and then pump the cooled air back into the vents, while pumping the warm air to the outside.
I'd do this stuff before you have a HVAC tech come out and charge you to go through and look at stuff. Odds are you can resolve it on your own without a $150 house call from a HVAC tech.