How to connect iMovie with external mic ?

Before doing anything with iMovie plug in your external mic to your Mac. When you go to System Preferences/Sound/Input you should see the external mic listed as an input device. Select it in the Input window.

Then go to iMovie and click on the microphone emblem to the left of the preview screen. Click on the settings emblem to the right of the red button. Click on Input Source in the drop down. You should see your external mic listed. In the screen shot it is AK5370. Click on it to select it. The name of the external mic will now appear in the input box. Then start your recording.

-- Rich

Hmmmm. Very puzzling that your internal mic is not working either.

Try redownloading iMovie. To do that To update/redownload iMovie 10, drag your

iMovie 10 app from the Applications folder into the trash, but do not empty the

trash. Sign in to the app store and open your purchases folder by

clicking on your name at the bottom of the app store side bar. You will see

your purchases displayed, including iMovie 10. Redownload/update iMovie from

there. If not successful, drag your present iMovie app out of the trash and return

it to the Applications folder.

-- Rich

I don't think that it is the Bluetooth connection, because the System Preferences panel does display the mic. But it might be. In my setup the eternal mic is plugged in by USB. However, I see from your screen shot of the Systems Preferences panel that the mic is not selected, i.e, it is gray rather than blue as in my screen shot. Try clicking on it to select it. It needs to be selected both in the preferences panel and the iMovie Voiceover system setting box. When you connect the mic the voiceover feature needs to be turned off.

I don't know if Catalina is the cause, since I am running Mojave. Sometimes with upgrades preferences get corrupted or changed. Try resetting your preferences. To do that open iMovie while holding down the Option and Command

keys and select to delete preferences in the box that appears. iMovie will open in a new library. Reopen your old library to get back to your projects. Now see if the voiceover feature will read your external mic.

You might also try creating a new project, putting a clip into it, and see if the voiceover feature works correctly with the external mic.

To cover the bases, have you confirmed that your external mic itself is functioning correctly and that your blue tooth is working. Also, does the voiceover feature work with the internal built in microphone. I see that your option box says "None".

-- Rich

If still not working, as a workaround you could try using the Voice Memos.app in the applications folder of your Mac. Then you could drag the audio clip into your iMovie project and sync it up with your video.

-- Rich