Can't listen to my exported recordings!

I’m sure I’m being completely silly but im having a problem with my exported recordings. I’ve looked online and no one else seems to have the same problem so ive come to the conclusion that I am being silly!
Having recorded a half an hour set, I attempted to export it to my Mac using iTunes. When it had exported into a .AIF file, it would not seem to play back. I hit the play button and it said that it was playing and it was about half an hour long but no sound?
I then tried to export it again but using drop box. It uploaded into my drop box and once again, no sound when I played it back. Can anyone help me?

Hi Georgia,

Are you using a controller? Or did this occur by just using djay?