Can't get MXF export to work in Nuendo 12 (HELP)


So basicaly I want to export an audio MXF of my 5.1 and when I export it, the lengh of the file is something like 535 hours long ( when I read it in VLC or others application). But it’s the good lengh when I import it again in nuendo and also the file is the right size ( 800 000Ko).
And finaly when I import in premiere the file just repeat the first 3s of audio again and again for several hours.

Do anyone know something about that or had a similar situation ?