iMovie 10.0.8 Voiceover stopped working

Hi There,

I was about to finish up making a tutorial video when my voiceover recording button stopped working. I didn't do anything out of the normal, when I went to re record a voiceover the record button just gives the the error sound whenever I click it. The mic is still recognized (when I talk the green/red audio bars activate) but it will not record. I am using my iPhone headphones and have tried unplugging and recording with my Mac Air's mic but I get the same error sound whenever I click the record button.

I thought I might of hit a max limit on iMovie's memory and deleted some audio/video files to no success. I am stumped can anyone help?

Thanks!