Extracting audio for Closed Captioning with CaptionSync can be affected by the type of encoding of your media files. This article shows some troubleshooting tips.
When uploading to the CaptionSync website, you may receive an error message in lieu of the successful upload page:
INTERNAL ERROR 003: Audio extraction failed.
Sometimes CaptionSync has issues extracting the audio from an MOV file. This typically happens when the audio track doesn't come in until later in the MOV (we're trying to extract audio from the beginning) or when there is more than one audio track (we don't mind a track having multiple channels however). The easiest fix to extract the audio to WAV from within QuickTime Player (you will need to upgrade to QuickTime Pro for $29.99)
Sound to Wave, (16 kHz, 16 bits, mono) then either submit that WAV or convert to MP3 and submit. .
When CaptionSync has issues extracting the audio from a WMV or WMA file, it's typically due to a corrupt header. This almost always happens when the media was created in the third-party application rather than on a Windows program. The fix is to transcode the file, using a genuine Windows program.
Sometimes CaptionSync has issues extracting the audio with certain FLV codec. The easiest fix to extract the audio to WAV (16 kHz, 16 bits, mono) or MP3 directly from the original media file.
For other issues please see the Problems with the Media File article.