track1 one gets cut off, by track two

I put a basic sample on track 1 and when I want to drop some drums on track two it cuts the note off on track 1...it does the same thing if I step edit.

mode program/ change samples from mono to poly

That was the first thing my friend did to see if that would stop it...

Did you check to see if you are maxing out on the polyphony?

turn it off and on. The program that you have with the samples on it should be re-made. Sometimes they glitch out...