Drum Rack Cant Play Two Layered Samples??

[theswiftone]

If I convert a drum loop to midi then it wont play samples that are layered on top of one another. Say a high hat is on the same beat as a snare it will only play one of them. The other one shows an output on the mixer, but if you solo it it's just a dodgy click unless you remove one of the midi notes. But drum rack works fine if you load one from the browser and layer sounds. Its just if converted from a loop to midi. Anyone else got this problem or know how to solve it????