I agree with BubbaGurt, it's awesome you can use the audio from Newgrounds and use it here.
I don't want to bug about this topic, but it would be cool to lip-sync other audio; for instance, uploading it to the game, like "Vector Stunt" does. Or maybe uploading it from a site that has a stash of videos like YouTube.
I don't know, I'm giving some feedback. Please ignore this if you already were told of this stuff I just suggested.