Power Seat Issues

[05GMC4DR]

So I got in the truck the other day and when I sat down it felt like I was sitting on the ground. So I hit the button to lift it back up and part way down the hill it felt like the seat was deflating.... so I hit the lever again and lifted the bottom of the seat back up again and had to do this several times through out the drive. It seems to work fine now, but every so often it seems to call back down. Anyone had this problem before? Is it an air bag/bladder in the bottom of the seat or is it an electric motor/gears that lift the seat? How do I fix it?

[superjim]

It uses electric motors and gears.