I actually have both x2 and x3 but for some reason i cant trigger the plugin sounds on the mpc and hear the notes  when I try with fm8 or session drummer im able to play the sounds before I record em triggered threw the mpc .
 
Idk but when I click on the east west keys with the mouse I can hear em just not when I try to play notes with the mpc
. im using win7 64b also idk if I should mention that im using crappy ass onboard sound vt1708s