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As I understand it, you don't have any sound even with headphones plugged in?
Thanks for clarifying. Does your MacBook have a removable battery?
The battery was replaced by Apple techs just three weeks ago.
That is fine. I am asking if it is removable by you.
Not that I can see. The case has screws, but I don't know what I would do to reach the battery. Why might the battery be the problem.
I'm trying to remember if I've had sound since. I have noticed no sound that I normally have in the last week or so.
No, I am just asking as the reset procedure is different.
Ok, are you chatting with me on the same computer?
Ok, you'll need to restart to do this reset. It is very important that you understand all the steps as they need to be done in order and rather quickly.
Shut down the computer normally. Once the computer is off, on the left side of the keyboard, you are going to hold down Shift, Option and Command (Apple). Press the power button and release all of them at the same time. Wait about 5 seconds. Press the power button again to turn the computer on. You may not hear a chime. Immediately hold down the following keys: Option + Command (Apple) + P + R. Keep these held for 2 chimes. If you don't hear any chimes after about 5-10 seconds, let go and let the computer boot up normally.
If you didn't hear chimes during that last step, there is something wrong physically and would need to be looked at by a service center.
OK. I'm printing your directions to make sure I do this right.
Great. Let me know how you make out with this.
I only got through the first step and heard sound when the computer booted. I tried a DVD and got sound. Hold on a minute while I check one other thing.
Take your time
We're in business again. Thanks.