MP3 Export is shorter

Hey guys,

Got a very strange issuue with cubase 8 pro. I am trying to export a wave file at 16bit 44.1 to an mp3 320kbit 44.1. Every time i export the mp3 comes a little shorter in length. It makes it impossible to create a loop in mp3.
The project setup is at 44.1

I am on an iMac 10.9.5

Any ideas why this is happening?

i have the same problem .
did you get any answers??