Basically what the title says. I can get A's and B's (and sometimes C's) on easy-medium Insanes and Hards, but I can't get any S or SS. I use a generic mouse (800 dpi) and a laptop keyboard and monitor. I don't have any problems with my sound/graphics, and I didn't install any new hardware. Is playing songs where I get B's and C's bad for my accuracy? Or are short combos natural?