Here is my issue. I have a Toshiba: Satellite. The speakers work fine. Typically, when I would plug in my headphones, the audio would mute on the exterior speakers and channel the sound to the headphones instead. Lately this has changed. Now when I plug in my headphones BOTH sets of speakers are pumping out sound. How do I restore this to the old setting, where when headphones are plugged in I only get sound out of them?