iMovie audio went silent

It appears that the Video Converter X2 app may be causing a conflict on your Mac, as the issue is not confined to iMovie. You might try removing Video Converter X2 to an external drive and see if that resolves it.

Meanwhile, you can try the following:

Resetting the System Management Controller

Try resetting the System Management Controller (but no longer available for the new M1, M2 computers):

Reset the SMC of your Mac - Apple Support

Resetting the NVRAM or PRAM

Try resetting the NVRAM or PRAM:

Reset NVRAM on your Mac - Apple Support

Contact Apple Support

If none of the above resolve your issue, contact Apple Support.  The techs there have the capability of

remotely accessing your computer that we cannot do here.  To contact apple support click on the Support

item above this forum’s screen.  Navigate to a place where you can enter your phone number.

-- Rich

Hi,

Not all Mp4 vids work with iMovie. It should be Mp4/AAC (AAC stands for Advanced Audio Coding). Open the video clip with QuickTimePlayer and do a Window/Show Movie Inspector. Check the audio format and see if it is AAC.

Even if it is AAC, run the clip through the free download Handbrake, that will re-render the clip to Mp4/AAC by default.

You can get Handbrake here:

https://handbrake.fr/

A simple way to do it is to open Handbrake and do a File/Open Source. Navigate to your video and choose it as the source from the resulting screen. Then do File/Start Encoding. Wait a couple of minutes for the conversion to

complete. Then save and import the converted clip into iMovie. See if you get sound.

-- Rich

Glad you got it solved. The bizarre audio issues apparently pointed to a software conflict.

— Rich