Been reading through all the previous posts but was just wondering what is the best solution to pan a sample from left to right without using the phaser effect. on the 303.
Also, what is the best way to mute a snare or something from your drum pattern? Is it best to record it live?

i'd suggest running your audio through a small, cheap mixer with pan controls (or triggering it from a daw) into the sp. if you really feel that panning is important, panning before you sample is the way to go.

the tremolo/pan effect on the 303 is ok for that aim.
a way to mute a sample is to apply the isolator effect:all the way down.