Wait five seconds, then press the 'Power' button. Files distortion Whether its video or audio files, they might suffer distortion if the right exporting and importing procedures are not followed. The solution will be converting the files to a format that is friendly to iMovie and the sound will play normally. Wait fifteen seconds, then plug it back in. Another cause can be incompatible format which is not supported by iMovie.

Desktop - Shut down the iMac and unplug the power cord.Release the 'Power' button, reinsert the battery, and plug in your computer to a power source.

Unplug the power adapter and remove the battery, then hold down the 'Power' button for five seconds.

Laptop with removable battery - Shut down your computer.

Using the left side of the built-in keyboard, hold down ⇧ Shift + Control + ⌥ Option while pressing the 'Power' button, then release all keys, and finally press the 'Power' button again.

Laptop with non-removable battery - Shut down your computer and plug it into a power source.

If none of the steps above solved your problem, reset the SMC: X Research source An issue with the SMC can prevent your power button from working properly, or cause general slowdowns. The SMC, or System Management Controller, handles many of the physical components on your Mac.

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