Ensure the download completed fully; M4V files often use H.264 codecs which provide high quality but can result in large file sizes.
Tools like HappyScribe can transcribe the audio to text if you need a written record.
To make the file more compatible with non-Apple devices like Android or Windows PC, you can convert it to MP4 .
Some video guides provide methods for repairing corrupted M4V files.
You can cut or trim the video using online tools like VEED.IO. File Integrity