I've been asked to transcribe some audio files that have been sent to me in MP4 format. My idea was to play the MP4s from Quicktime and set up dictation in Text Edit to record/transcribe it. The moment I start dictation (fn fn), it shuts off the built-in audio. For some strange reason, I have also tried playing the file on one Mac and recording via dictation on another, but it doesn't work - records the odd word here and there. Is there an automatic way to do this?