How to correct rejected audio files

 

First of all, make sure that your audio is a true .wav file. Renaming the file extension from (for instance) .mp3, .m4a or .aiff to .wav will not magically make the file a true .wav file. You must make sure that the file is encoded as a waveform audio file format, sometimes also uncorrectly called “Audio for Windows/Windows Audio”. This is done by exporting the audio from your editing, mastering or recording software as an LPCM .wav file. Make sure the "BWF" (Broadcast Wave) checkbox (if present in your audio software) remains unchecked.

Note that some audio editors and Digital Audio Workstations (DAWs) do not export clean .wav files, but include additional data in the file header. Logic Pro X is notorious for this and will practically always lead to rejection by our system.

 

Secondly, make sure that the audio has the correct resolution. For regular streaming and download platforms, the bit depth should be 16 bits and the sampling rate 44.1 kHz, also known as "CD quality". For the sake of this article, we refer to it as standard resulution.

If your audio project has a higher resolution, make sure to apply the correct dithering and sample rate conversion during or before exporting.

That said, you can upload higher resolution audio (up to 24 bit, 96k kHz) in the portal, but it will automatically be converted to standard resolution by the system's encoder.

 

If you have a correctly exported wav file (which may play back perfectly fine in your media player) and it is still getting rejected, it may be that your particular file is faulty or corrupt.

 

The most common cause of rejection is a faulty/corrupt file.

 

The .wav format contains the uncompressed audio, but also some extra data, such as the file header and metadata. There is no strict regulation as to what data can be stored in a .wav file and most software audio players just ignore any non-audio bits and play back the uncompressed audio stream as-is. However, encoders and conversion algorithms (such as the ones employed in our release ingestion system) are much more sensitive to stray data and will fail to recognise the file. They need a “clean” header and audio bits.

 

To fix this problem, you can use a free piece of software called Audacity (https://www.audacityteam.org/), an Audio Editor which is available for Windows, Apple MacOS and Linux. If you have your own audio editor, such as Wavelab, Audition, Samplitude or Sound Forge, the principles are the same as described below.

Opening the audio file in Audacity and subsequently exporting it will strip the superfluous data from the audio file and ensure it has a clean header.

 

Proceed as follows:

1. First make sure Audacity handles your audio file correctly. Click on “Edit” -> “Preferences” and set the “Quality” settings like below. You only have to do this once; the settings will be saved in the program.

 

2. Open your faulty .wav file in the program (“File” -> “Open” or drag-and-drop).
3. Export the audio by choosing "Export" -> "Export as WAV" in the "File" menu.

4. Make sure the "Encoding" is set to "Signed 16-bit PCM".

 

Now, your file should be correct. Re-upload it in the portal or re-supply it to us.