When you open the camera, you notice that there is a microphone inside. Revo sells an RJ12 to power/BNC balun, but there is no version of that with audio. A call to their tech support confirms that the camera does indeed have audio, but they have no way to output that to normal audio jacks. I suppose they only want you to have audio if you're using a complete Revo system. Other than that, the cameras have a decent picture. They really need to put on some standard plugs though.. why on earth should someone have to buy an adapter when every other security camera on the market has standard plugs??