Failure processing m4a audio files, but not aac files with the same content

[perotinus]

I'm running into a strange issue with processing prerecorded audio files. I have some m4a audio files that are generated by an iOS application, but Deepgram will not process them. ffmpeg understands them, they work in other media players, and they look largely the same (at a codec and container level) as the m4a file in the Deepgram test app for prerecorded audio.

However, If I extract the same audio stream from the m4a file and put it into an aac file with ffmpeg, the transcription works fine, so I don't think this is a problem of corrupted audio data.

Deepgram product: Text to speech: local file
Successful request ID: af199a52-a96f-4097-b24e-c9a92c520b4c
Failed request ID: a7cbc765-ef8d-42b9-b89c-55c1b2c01a5f

Repro steps:

• Code and audio data for repro: repro.tgz

1. Download and extract the repro archive.
2. Set up the environment per the instructions in the README file
3. Replace in index.js with a valid Deepgram API key
4. Replace the audio file in index.js with broken.m4a
5. Run the script ($ node index.js)

Expected: transcript
Actual: error DeepgramApiError: {"err_code":"Bad Request","err_msg":"Bad Request: failed to process audio: corrupt or unsupported data","request_id":"a7cbc765-ef8d-42b9-b89c-55c1b2c01a5f"}

Now, try again with same_data.aac (replacing it in index.js) and it transcribes correctly. I generated same_data.aac as follows:

$ ffmpeg -i broken.m4a -acodec copy same_data.aac

Is there a reason that the M4A files aren't working correctly? I'm not doing anything particularly special to generate them in the iOS app.

[deepgram-community[bot]]

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[deepgram-community[bot]]

Hey there! It looks like you haven't connected your GitHub account to your Deepgram account. You can do this at https://community.deepgram.com - being verified through this process will allow our team to help you in a much more streamlined fashion.

[deepgram-community[bot]]

It looks like we're missing some important information to help debug your issue. Would you mind providing us with the following details in a reply?

• The deepgram product you are using (e.g Speech to Text, Agent API)
• A request ID that triggered your error or issue.

[perotinus]

Thank you bot! I added request IDs, the relevant product and a easier-to-follow set of repro steps.