Unable to import AVCHD files into iMovie

Import the AVCHD folder to your desktop. Open the folder and navigate to the mts files that are your movies and photos. Copy-drag them to your desk top. Use the free download Handbrake to convert them to Mp4/AAC files. Import the converted files into iMovie.

— Rich

Check this website to determine whether your Sony is an Apple supported camera:

https://support.apple.com/en-us/HT204202

Some users have had difficulty importing AVCHD files and found that the problem was solved by removing from their Macs the obsolete A52 codec and/or the Perian app and Perian.prefPane. Take a look at this rather long thread. The discussion about Perian begins on page 2.

https://discussions.apple.com/thread/8123734?answerId=33050087022&page=2

-- Rich

I don’t have my Mac at hand right now, so unable to check my audio folder re plugins. The A52 codec, if it exists on your Mac, would be located in Library/Audio/Plug-ins/Components. So if it is not in there you don’t have it.

iMovie should be able to convert AVCHD mts files automatically. Have you tried using the Image Capture app on your Mac to import the AVCHD folder to your desktop? Or tried to import into the Photos app?

— Rich

O.K. You've got it. It's a workaround but at least functional until something better comes along.

-- Rich

I checked my Mac and I dont have any audio plugins at all in my Audio folder.

-- Rich