How do I turn a midi loop into a perfect audio loop?

I have some drum loops that are in midi format. I want to convert them into a audio file loop. When I bounce the midi file or export it to and audio file the audio starts a little after the midi hits. Basicly it adds an extra silent audio at the begining of the loop and it does not start at the beggining. To make it a perfect loop like the midi I always have to cut off the beggining until the loop really starts. Sorry about my bad explination. I just want to get my little drum loops in midi to be converted to the same thing but in a audio file without the added delay at the begging of the audio file. I am doing this to a lot of loops to make them apple loops. So what am i doing wrong? Or does this allways happen? And is they any quick or better way to do this? It would really help a lot! Thank you!