midi program change

i got a problem. im sync to fruityloops. in the pc field ,on the mpc. when i change the number, i can hear,an see the different snyths,change in fruityloops, thats not the problem. but when i go to a different trk. on the mpc, an change the pc field ,to a differnt sound, the 1 i recorded on the trk. befor, change as well, to the sounds of the new trk. how, can i use different snyths, without the program,changing up on me?

Make sure the MIDI channels for each track are seperate.

I've never used Fruity Loops, but I would assume that the program could accept messages on more than one channel, right? If not, then you're screwed, but if so, just make sure each track is on a seperate MIDI channel, and then your PC changes should stay independant of eachother.