Solve : I Cannot Change The Volume On iMac OS X 10.7.5 At All!?

1.	Solve : I Cannot Change The Volume On iMac OS X 10.7.5 At All!?
Answer» My iMac has been running fine for about 3 years now. A great device it had been, helped me a lot with my work. But RIGHT after I updated my device to OS X 10.7.5, I cannot change the volume at all! When I press on the F11 or F12 button for the volume control, the volume bar shows. The volume bar is always full, but a little cross shows below the volume bar, and I cannot change the volume. Also although the sound bar is full, there is absolutely no sound at all! I tried to change the volume in "System Setting". The is an option the change it, but it is also greyed out. I found that some other users also got this problem when they updated to OS X 10.7.5, but I found no useful answers. Any help is APPRECIATED! Thanks. Hello. My Mac is STILL STUCK like that. And I can't hear any sound from my Mac, which is very annoying. Anyone got a SOLUTION yet? Thanks. Whitebeard1

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