MBP Mousepad Issues

so i just got my first mac, a macbook pro, and on mine the 2-finger scroll feature works very poorly, with the screen moving sporadically, sometimes even being able to give it multiple caresses without the screen even budging. i've noticed it responds best to a light touch, but still: on a 2100 dollar piece of kit you shouldn't have to even think about it.

to make matters worse, the pointer *moves* when you tap it, so if you try to tap-scroll, the pointer's off the scroll arrow within a few taps. this is utterly unacceptable.

i've lurked around a lil before posting this, and ironically the only things i've heard about the mousepad is how excellent it is, and how awesome the scrolling. i bought the mac because of the preference of OSX for music production/performance, but it's replacing my old daily driver, an old low-budget toshiba whose pad motion is tight as a drum, you can tap all day and never go off the mark.

mine's a refurbished model, could that have something to do with it? anyone else have this problem with their MBP trackpad?