imovie file no sound

Try converting the movies to Mp4/AAC with the free download, Handbrake. Do that even if the codec already is indicated to be Mp4/AAC. Re-rendering often cures audio issues.

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.

-- Rich

O.K. Nothing to do but try a few things to see if we can isolate the problem.

Open your exported .m4v movie in QuickTimePlayer and do a Window/Show Movie Inspector. In the movie inspector box that appears, what audio and video format is shown? It would be helpful if you could post a screen shot of the movie inspector box. Does the movie play with audio on your desktop in QuickTimePlayer?

Open the movie in Handbrake again. When you click on the Audio button, does it display an audio format in the codec box? If so, what is the codec shown to be?

Also, in what version of iMovie did you create the movies? iMovie 9 or 10? Was the audio track initially embedded in the the video clips, or was it added in a separate audio track?

Try importing your .m4v movie into the timeline of a newly created iMovie project. Then click on the Settings button above and to the right of the timeline. In the Settings dialogue box that appears, click on Audio:Show Waveforms. Also use the settings box slider to increase the clip size. Now look at the movie clip in the timeline. Does it display wave forms in the blue stripe at the bottom of the clip?

-- Rich