I went to turn the volume on my MBP up today (it's only ~3 months old, running Leopard), and the little volume image that comes up had the speaker image grayed out, and the little "no" circle displayed. However when I plug in headphones, they work fine, and the audio controls are fully functional. Sans headphones though, it's as if the drivers for my MBP speakers have disappeared. I've never had any issues with the audio controls or speakers on my computer. I often use headphones or have the speakers muted, as I take the computer with me to class. This is my first Mac, and this is the first problem I have encountered with it. I've gone into Preferences > Sound > Output, and the only thing displayed is 'Digital Out', so it appears the internal speakers have disappeared. Can anyone point me in the right direction? How do I reinstall the driver (assuming it's that easy), or solve the problem otherwise? And any insight as to why this may have happened would be helpful as well. Again, this is my first Mac, so I'm fairly ignorant when it comes to troubleshooting, and the location and installing of drivers and such. Any help would be greatly appreciated, and please let me know if more information is needed.