Can't get out of real time mixdown

Nuendo
1

Hi again,
I did an audio mixdown and checked the real time option. All went fine. On my next mixdown I unchecked it, but it was still real time. It seems to be stuck. Has anyone seen this?
Thanks!
Eric

2

Are you using any External VSTi or effects?

DG

3

Nope, nothing external all in the box.