Audio Dropout Mid Clip

I'm editing a project on Premiere CS6 and I'm having an odd audio problem. For long clips the audio simply disappears midway through the clip. I know the audio is there because I play play it on the camera and in Final Cut.

My theory is that I was running out of space on my laptop cache and it simply gave up on those audio clips. Premiere seemed to act oddly when conforming by going back to clips several times but I got no error message.

Any ideas what this problem is and how I can remedy?