For some reason the sound is disabled on my Mac. I'm running 10.5.4. I don't know what happend. I was using it earlier and sound was working. Went away for a while, came back and got ready listen to something and I noticed no sound. I clicked on the volume control on the menu bar and it's disabled. I have volume control on my keyboard so I pressed it and the volume "image" appears on the screen with a "NO sign". i.e. - the circle with the diagonal line through it. First tried logging off...didn't help. I restarted...didn't help. I looked in System Preferences don't see any global enable/disable item. In System Preferences -> Sound I click Output...the is one line under choose a device for sound output. I select it, but under the "Settings for selected device:" it says "The selected device has no output controls". Not sure what that is telling me. Also the Output volume slider (on that same page) is disabled... Any help pointers would be greatly appreciated.