A: Thanks for asking! If you only Enhance your audio in Resound (use AI to mix and master) then the file will be the same length as what you upload, and your audio and video will be in sync. However, if you cut filler sounds and long silences (as Resound will recommend), then the file will be different. If you wish to edit the content and the mix, then I recommend uploading your MP4 video to Resound and exporting as an MP4 - this allows you to edit the audio and video, keeping them both in sync. This feature is in beta, so please share feedback if you test it out so we can keep improving. Learn more about the beta mp4 video exports here: https://help.resound.fm/en/articles/8709306-how-to-export-mp4-videos-from-resound. Thanks!