I just bought a 2005 Ford Focus?

I just bought a 2005 ford focus ZX4 ST yesterday for my first car. I really like the car but I have a few questions. It has the Sony audiophile package so it has a subwoofer in the trunk but the subwoofer isn't working. Is there some way to turn it off and on? Also it looks like there's some way to adjust the height of the driver seat manually but I can't figure it out? Any held would be appreciated.

I forgot to ask this. There's an aux button but there's no auxiliary input?