Vocal Sync wont load in Platinum

Hey everyone,
 
Ive been working on a project for most of the day today (using Vocal Sync) with out any issues.
 
About an hour ago, i continued on to the last vocal performance and tried to load VS as I usually do but the "knob" didnt pop up.
 
When I select the single track, right click and go to region effects and attempt to load VS, it says its "mixing down" the audio for a second then does nothing. I went up to the "edit" menu and it does not give me the option to "undo" the region effect, its as if it was never applied at all.
 
I tired on other tracks in this project and got the same result. I opened up another project, and it seemed to work fine.
 
Has anyone come across this before?!