PR CS6 MXF OP1A audio export problem

Hi,

I work as an editor for a big broadcast cooperation.

Since we need to deliver MXF's with 4 channel audio our department is very interested in moving over from FCP to PR CS6.

After the first couple test instantly we came accross one major problem. The render that we did with the settings as seen below got some sort of static. A ratteling noise that became louder every 12 sec. This is the only thing that stands in our way to move over to a Adobe only pipeline.

Any help will be highly appreciated!

Thanks,

Rein