overdub nightmare!!!

Hallo everybody...i'm a brand new mpc2500 owner with a brand new list of problems...one overall is that when i try to make a simple beat step by step(first i record the kick than the snare and the hi hat)first i push play and rec. together to play the kick in the first 2 bars then in automatic goes in overdub to record the next instrument(ie the snare)and so on for the hi hat. The point is that if i have to sounds playing together, the last one will mute the one before(ie. the hi hat mute the kick or the snare when they are in the same position).I know for shure it will be a very simple problem but at the moment i really don't know how to solve it.I hope i've been clear with my english and i hope to have a massive feedback from all of you guys...thanks

Troubled"Dj Zac1"on the MPC!!!

very simple, go to program mode and change mono to poly up in the right hand corner. Should solve the problem.

Great Man!!!!it works...thanks a lot...I will keep u on mind for my next troubles!!!